CAIRO, Egypt - A group calling itself "The Secret Organization of al-Qaida in Europe" posted a claim of responsibility for Thursday's blasts in London, saying they were in retaliation for Britain's involvement in Iraq and Afghanistan.
The authenticity of the message could not be immediately confirmed.
The statement, which also threatened attacks in Italy and Denmark, was published on a Web site popular with Islamic militants, according to Elaph, a secular Arabic-language news Web site, and Der Spiegel magazine in Berlin, which published the text on their Web sites.
"Rejoice, Islamic nation. Rejoice, Arab world. The time has come for vengeance against the Zionist crusader government of Britain in response to the massacres Britain committed in Iraq and Afghanistan," said the statement, translated by The Associated Press in Cairo. The AP was unable to access the Web site where it was posted, which was closed quickly after the reports.
The group al-Qaida in Europe claimed responsibility for the last major terror attack in Europe: a string of bombs that hit commuter trains in Madrid, Spain in March 2004, killing 191 people. Two days after that attack, a video was found in a trash can outside a Madrid mosque with a statement purported to be from the group's spokesman, called by the nickname "Abu Dujan al Afghani."
In the new statement, the group said "the heroic mujahedeen carried out a blessed attack in London, and now Britain is burning with fear and terror, from north to south, east to west."
"We warned the British government and the British people repeatedly. We have carried out our promise and carried out a military attack in Britain after great efforts by the heroic mujahedeen over a long period to ensure its success."
"We continue to warn the governments of Denmark and Italy and all crusader governments that they will receive the same punishment if they do not withdraw their troops from Iraq and Afghanistan," the statement went on.
It was signed "The Secret Organization of al-Qaida in Europe."