The official cause of the tragedy is unknown, but there are reports the fire may have been caused by a band's pyrotechnics display at the Kiss club in Santa Maria, 300 kilometres west of the state capital, Porto Alegre.
The Diário de Santa Maria website said the fire broke out around 2 a.m. local time Sunday.
It appears sparks ignited acoustic tiles lining the ceiling, Andrew Downie, a correspondent for Time magazine in Brazil, told CBC News. The blaze quickly spread and thick smoke filled the venue.
Brazil nightclub fire death toll rises to 245 - World - CBC News