Heavy rain in northeast Brazil broke open a dam, releasing a wall of water that destroyed 500 homes and killed four people, officials said Thursday.
The government of the northeastern state of Piaui said the damage wrought Wednesday by the breach outside the town of Cocal left an estimated 2,500 people homeless.
Four people, including a 12-year-old girl, died when the waters in the Pirangi river rose suddenly, up to 20m in some parts, civil defense officials said in a statement.
"It was a real tsunami," said state governor Wellington Dias after he visited the area.
He added that he was talking with the federal government about providing aid to those affected.
Flooding and mudslides in northeast Brazil over the past few weeks have left 57 people dead.