The Queen has sent her "sincere condolences" to the families of those killed in the Tunisian beach massacre.
The monarch said she and the Duke of Edinburgh were "shocked" by Friday's gun attack and she also offered their "deepest sympathy" to the injured.
Officials fear the UK death toll is likely to be in the mid to high 20s, out of 38 victims in total. Three of the victims were three generations of the same family.
Relatives of others still missing are anxiously awaiting any news of their loved ones.
Daniel Welch, who has not heard from his grandfather John since the attack, said "we can only expect the worst".
It is the biggest terrorist attack on British citizens since the 7/7 bombings, the tenth anniversary of which is Tuesday next week.
Tunisia attack: Queen offers condolences to victims' families
BBC News
28 June
A local boy with floral tributes to tourists gunned down by Islamist Seifeddine Rezgui
The Queen has sent her "sincere condolences" to the families of those killed in the Tunisian beach massacre.
The monarch said she and the Duke of Edinburgh were "shocked" by Friday's gun attack and she also offered their "deepest sympathy" to the injured.
Officials fear the UK death toll is likely to be in the mid to high 20s, out of 38 victims in total.
Relatives of others still missing are anxiously awaiting any news of their loved ones.
Daniel Welch, who has not heard from his grandfather John since the attack, said "we can only expect the worst".
Simon Boon is another Briton desperately seeking information.
He says he saw his sister Allison Heathcote on news channels being stretchered off the beach on a sunbed, but had very little information from the Foreign Office, and had to rely on news websites and phoning hospitals in Sousse to find out what happened.
She had received two gunshot wounds, had undergone surgery and was now critical, he said.
"My brother-in-law - we still have no information. Originally the Foreign Office said he was with his wife but no hospitals have any records," he said.
"Nearly 48 hours on, we're none the wiser."
The Foreign Office has put the official UK death toll at 15, but ministers have said this is likely to rise. An unspecified number have been injured.
Other countries affected by the shooting carried out by 23-year-old Seifeddine Rezgui, who had links with Islamic State, include Belgium, Germany and Ukraine. Three people from Ireland were also killed.
The Foreign Office has updated its travel advice to warn that further terrorist attacks in Tunisia are possible, and urged people to be vigilant.
Scotland Yard says its investigation into the Tunisian attack is "likely to be one of the largest counter-terrorism deployments" since the London 7/7 bombings in 2005.
The Met said the operation currently involves more than 600 officers and staff, with many sent to British airports to speak to returning holidaymakers. It has already deployed 16 officers to Tunisia, including forensic specialists and family liaison officers.
'Won't have had phones'
Speaking after she chaired a meeting of the government's emergency Cobra committee, Home Secretary Theresa May said Foreign Office staff were working round the clock in Tunisia and a 24-hour crisis centre was up and running in the UK.
She added that she had seen no evidence to indicate the beach was targeted because of the high number of British holidaymakers.
Downing Street's flags are flying at half-mast in memory of the British victims
The Foreign Office's flag was also lowered
Several relatives have expressed concern about the lack of information from both the government and tour operators.
Holly Graham, from Perth, whose parents Billy and Lisa are missing, said: "Thomson are like they're just reading off a piece of paper.
Foreign Office - they just tell you they've got no information."
The home secretary suggested officials were having difficulty identifying the British victims as many were not carrying identification.
Mrs May said many would not have had passports with them on the beach and some victims were being moved between hospitals in the country.
"What's important is that the information is absolutely 100% correct when it is given to a family," she told BBC One's Andrew Marr Show.
"If you can imagine, because of the circumstances of the attack, people won't have had documents with them, they won't necessarily have had phones."
The British victims have not been officially identified but the names of some have been confirmed by friends and family:
Carly Lovett, 24, a beauty blogger and photographer from Gainsborough in Lincolnshire who was first to be named
Sue Davey and her partner Scott Chalkley, both in their 40s, whose deaths were confirmed by their respective sons
Adrian Evans, his father, 78-year-old Patrick Evans and nephew Joel Richards, 19, from Wednesbury.
Bruce Wilkinson, 72, from Goole in Yorkshire.
Lisa Burbidge, in her 60s, from Whickham, Gateshead
Claire Windass, 54, from Hull, was on the beach with her husband, who survived
Prayers have been said for Jim and Ann McQuire, from Cumbernauld
Trudy Jones, 52, from Blackwood, Caerphilly county.
Three victims from the same family
One British victim was named as Adrian Evans, who worked for Sandwell Council as a manager in the gas services department.
A council source described the news as "horrendous" and said their thoughts were with the family and council colleagues.
The third victim was later named as his nephew, 19-year-old local football referee Joel Richards.
Mr Richards, who played for James Connollys GFC in Warwickshire, was described by friends on social media as "ambitious" and "one of a kind".
Connollys GFC released the following statement last night: "James Connollys GFC is devastated to learn of the death of one of our players, Joel Richards, during the horrific attack in Tunisia."
Patrick Evans, 78, who was Mr Richards' Grandfather and Mr Evans' father, was also killed.
Carly Lovett, Adrian Evans and Mr Evans' nephew Joel Richards, left to right
Sue Davey and Scott Chalkley
At the scene: Mark Lowen, BBC News, Sousse
There's little trace of the horror - just a sunbed draped in flowers.
The beach where Seifeddine Rezgui stood on Friday, pulled a Kalashnikov from his parasol and unleashed Tunisia's worst ever terror attack, has already reopened.
Camera crews capture the spot; passers-by pause for a moment. But the emotional scars of the tragedy that took place will live on for a generation.
Tunisia attack: Queen offers condolences to victims' families - BBC News
Get tough and defend our borders and cities, writes NIGEL FARAGE, leader of Ukip
By Nigel Farage, Ukip Leader and MEP for South East England
28 June 2015
Daily Mail
Need for change: Nigel Farage says we face threat to civilisation
The events of Friday proved what many of us had feared for so long. We face one of the biggest threats to our way of life and our civilisation that we have ever seen.
Our approach to this issue and our behaviour needs to change right now.
I was considering going to Kenya this summer as a keen deep-sea angler but have taken the view that it is just not safe. I suspect tens of thousands of other British citizens will now be reviewing their travel plans for the summer as well.
Decisions such as this are easy. But what is more worrying is the threat which in some cases is already on our shores and, if we are not careful, will be added to by the human tide that is coming across the Mediterranean.
I have been arguing for some months in the European Parliament that the EU’s Common Asylum Policy is a terrible mistake. It sets the terms for who qualifies so broadly that it says to anyone in Africa: ‘If you come, you can stay.’
Already Northern European countries are saying no to Commission President Juncker’s idea that the burden should be shared by member states.
The numbers involved have the potential to mark an exodus from Africa of biblical proportions.
In the UK, the Government comforts us by saying we are opted-out of this scheme. But as events in Calais last week show, it is entirely possible for illegal immigrants to get to Britain. If they do, their chances of being caught are slim and if they are caught the likelihood is that they won’t be deported.
It is time to get tough and defend our borders properly. We must put in place a checking system at Dover for every car and lorry coming into the UK. The utopian dream of free movement has hit the buffers.
A second problem we face is that if Italy cannot get other countries to accept large numbers of migrants, then they have a simple way out. All they have to do is issue an EU passport to migrants and then anyone can come to the UK legally under EU rules.
I firmly believe the EU should follow the example of Australia which, in 2008, made it clear that migrants arriving by boats would not make Australia their home.
The boats stopped coming. The drownings stopped too.
This issue is far more serious than the usual debate about pressure on public services. This is now one of security.
Threat: A boy holds a Tunisian flag as he stands near bouquets of flowers laid at the beachside of the Imperiale Marhabada hotel. Farage said it was time to 'defend our borders'
Security: Police officers detain a migrant during a clash between migrants wanting to get into the UK and a lorry driver at the ferry port of Calais, as Farage warned people getting into UK illegally represent security threat
I would pay tribute to our security services. We know over 300 jihadis who have fought for Islamic State abroad are already back in the UK. Around two dozen of those have planned attacks since returning, but have been thwarted.
I suspect one of the reasons we haven’t had another atrocity on British soil is because our security services have done such a good job.
We must ensure our security services are given the tools they need to keep us safe. But the threat comes from beyond our shores too.
Britain must bear some culpability for destabilisation abroad. It was our government who foolishly bombed Libya into oblivion. It was a terrible mistake.
Where do the people start their journeys across the Med from now? Libya, a country with a growing IS element. IS have already said that they intend to flood the continent with 500,000 jihadi fighters. Even if that only amounts to 5,000, it is still an alarming prospect.
The Greeks and Italian authorities have absolutely no means of screening the individuals who arrive via boat for links with terrorism and extremism.
When I make the argument we must get tough on border controls to ensure the safety of British citizens, I am told I’m not being compassionate. We must not let our compassion imperil our civilisation.
I believe we are making one of the greatest mistakes in our history.
The monarch said she and the Duke of Edinburgh were "shocked" by Friday's gun attack and she also offered their "deepest sympathy" to the injured.
Officials fear the UK death toll is likely to be in the mid to high 20s, out of 38 victims in total. Three of the victims were three generations of the same family.
Relatives of others still missing are anxiously awaiting any news of their loved ones.
Daniel Welch, who has not heard from his grandfather John since the attack, said "we can only expect the worst".
It is the biggest terrorist attack on British citizens since the 7/7 bombings, the tenth anniversary of which is Tuesday next week.
Tunisia attack: Queen offers condolences to victims' families
BBC News
28 June
A local boy with floral tributes to tourists gunned down by Islamist Seifeddine Rezgui
The Queen has sent her "sincere condolences" to the families of those killed in the Tunisian beach massacre.
The monarch said she and the Duke of Edinburgh were "shocked" by Friday's gun attack and she also offered their "deepest sympathy" to the injured.
Officials fear the UK death toll is likely to be in the mid to high 20s, out of 38 victims in total.
Relatives of others still missing are anxiously awaiting any news of their loved ones.
Daniel Welch, who has not heard from his grandfather John since the attack, said "we can only expect the worst".
Simon Boon is another Briton desperately seeking information.
He says he saw his sister Allison Heathcote on news channels being stretchered off the beach on a sunbed, but had very little information from the Foreign Office, and had to rely on news websites and phoning hospitals in Sousse to find out what happened.
She had received two gunshot wounds, had undergone surgery and was now critical, he said.
"My brother-in-law - we still have no information. Originally the Foreign Office said he was with his wife but no hospitals have any records," he said.
"Nearly 48 hours on, we're none the wiser."
The Foreign Office has put the official UK death toll at 15, but ministers have said this is likely to rise. An unspecified number have been injured.
Other countries affected by the shooting carried out by 23-year-old Seifeddine Rezgui, who had links with Islamic State, include Belgium, Germany and Ukraine. Three people from Ireland were also killed.
The Foreign Office has updated its travel advice to warn that further terrorist attacks in Tunisia are possible, and urged people to be vigilant.
Scotland Yard says its investigation into the Tunisian attack is "likely to be one of the largest counter-terrorism deployments" since the London 7/7 bombings in 2005.
The Met said the operation currently involves more than 600 officers and staff, with many sent to British airports to speak to returning holidaymakers. It has already deployed 16 officers to Tunisia, including forensic specialists and family liaison officers.
'Won't have had phones'
Speaking after she chaired a meeting of the government's emergency Cobra committee, Home Secretary Theresa May said Foreign Office staff were working round the clock in Tunisia and a 24-hour crisis centre was up and running in the UK.
She added that she had seen no evidence to indicate the beach was targeted because of the high number of British holidaymakers.
Downing Street's flags are flying at half-mast in memory of the British victims
The Foreign Office's flag was also lowered
Several relatives have expressed concern about the lack of information from both the government and tour operators.
Holly Graham, from Perth, whose parents Billy and Lisa are missing, said: "Thomson are like they're just reading off a piece of paper.
Foreign Office - they just tell you they've got no information."
The home secretary suggested officials were having difficulty identifying the British victims as many were not carrying identification.
Mrs May said many would not have had passports with them on the beach and some victims were being moved between hospitals in the country.
"What's important is that the information is absolutely 100% correct when it is given to a family," she told BBC One's Andrew Marr Show.
"If you can imagine, because of the circumstances of the attack, people won't have had documents with them, they won't necessarily have had phones."
The British victims have not been officially identified but the names of some have been confirmed by friends and family:
Carly Lovett, 24, a beauty blogger and photographer from Gainsborough in Lincolnshire who was first to be named
Sue Davey and her partner Scott Chalkley, both in their 40s, whose deaths were confirmed by their respective sons
Adrian Evans, his father, 78-year-old Patrick Evans and nephew Joel Richards, 19, from Wednesbury.
Bruce Wilkinson, 72, from Goole in Yorkshire.
Lisa Burbidge, in her 60s, from Whickham, Gateshead
Claire Windass, 54, from Hull, was on the beach with her husband, who survived
Prayers have been said for Jim and Ann McQuire, from Cumbernauld
Trudy Jones, 52, from Blackwood, Caerphilly county.
Three victims from the same family
One British victim was named as Adrian Evans, who worked for Sandwell Council as a manager in the gas services department.
A council source described the news as "horrendous" and said their thoughts were with the family and council colleagues.
The third victim was later named as his nephew, 19-year-old local football referee Joel Richards.
Mr Richards, who played for James Connollys GFC in Warwickshire, was described by friends on social media as "ambitious" and "one of a kind".
Connollys GFC released the following statement last night: "James Connollys GFC is devastated to learn of the death of one of our players, Joel Richards, during the horrific attack in Tunisia."
Patrick Evans, 78, who was Mr Richards' Grandfather and Mr Evans' father, was also killed.
Carly Lovett, Adrian Evans and Mr Evans' nephew Joel Richards, left to right
Sue Davey and Scott Chalkley
At the scene: Mark Lowen, BBC News, Sousse
There's little trace of the horror - just a sunbed draped in flowers.
The beach where Seifeddine Rezgui stood on Friday, pulled a Kalashnikov from his parasol and unleashed Tunisia's worst ever terror attack, has already reopened.
Camera crews capture the spot; passers-by pause for a moment. But the emotional scars of the tragedy that took place will live on for a generation.
Tunisia attack: Queen offers condolences to victims' families - BBC News
Get tough and defend our borders and cities, writes NIGEL FARAGE, leader of Ukip
By Nigel Farage, Ukip Leader and MEP for South East England
28 June 2015
Daily Mail
Need for change: Nigel Farage says we face threat to civilisation
The events of Friday proved what many of us had feared for so long. We face one of the biggest threats to our way of life and our civilisation that we have ever seen.
Our approach to this issue and our behaviour needs to change right now.
I was considering going to Kenya this summer as a keen deep-sea angler but have taken the view that it is just not safe. I suspect tens of thousands of other British citizens will now be reviewing their travel plans for the summer as well.
Decisions such as this are easy. But what is more worrying is the threat which in some cases is already on our shores and, if we are not careful, will be added to by the human tide that is coming across the Mediterranean.
I have been arguing for some months in the European Parliament that the EU’s Common Asylum Policy is a terrible mistake. It sets the terms for who qualifies so broadly that it says to anyone in Africa: ‘If you come, you can stay.’
Already Northern European countries are saying no to Commission President Juncker’s idea that the burden should be shared by member states.
The numbers involved have the potential to mark an exodus from Africa of biblical proportions.
In the UK, the Government comforts us by saying we are opted-out of this scheme. But as events in Calais last week show, it is entirely possible for illegal immigrants to get to Britain. If they do, their chances of being caught are slim and if they are caught the likelihood is that they won’t be deported.
It is time to get tough and defend our borders properly. We must put in place a checking system at Dover for every car and lorry coming into the UK. The utopian dream of free movement has hit the buffers.
A second problem we face is that if Italy cannot get other countries to accept large numbers of migrants, then they have a simple way out. All they have to do is issue an EU passport to migrants and then anyone can come to the UK legally under EU rules.
I firmly believe the EU should follow the example of Australia which, in 2008, made it clear that migrants arriving by boats would not make Australia their home.
The boats stopped coming. The drownings stopped too.
This issue is far more serious than the usual debate about pressure on public services. This is now one of security.
Threat: A boy holds a Tunisian flag as he stands near bouquets of flowers laid at the beachside of the Imperiale Marhabada hotel. Farage said it was time to 'defend our borders'
Security: Police officers detain a migrant during a clash between migrants wanting to get into the UK and a lorry driver at the ferry port of Calais, as Farage warned people getting into UK illegally represent security threat
I would pay tribute to our security services. We know over 300 jihadis who have fought for Islamic State abroad are already back in the UK. Around two dozen of those have planned attacks since returning, but have been thwarted.
I suspect one of the reasons we haven’t had another atrocity on British soil is because our security services have done such a good job.
We must ensure our security services are given the tools they need to keep us safe. But the threat comes from beyond our shores too.
Britain must bear some culpability for destabilisation abroad. It was our government who foolishly bombed Libya into oblivion. It was a terrible mistake.
Where do the people start their journeys across the Med from now? Libya, a country with a growing IS element. IS have already said that they intend to flood the continent with 500,000 jihadi fighters. Even if that only amounts to 5,000, it is still an alarming prospect.
The Greeks and Italian authorities have absolutely no means of screening the individuals who arrive via boat for links with terrorism and extremism.
When I make the argument we must get tough on border controls to ensure the safety of British citizens, I am told I’m not being compassionate. We must not let our compassion imperil our civilisation.
I believe we are making one of the greatest mistakes in our history.
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