Floodwater, resulting from heavy rains that began last Friday, damaged three bridges and caused a dam to overflow, submerging buildings across the city.

Most of the victims were children.

"I think in the process a lot of houses were washed away by the rainwater," said Umar Mairiga, a Red Cross official.

He said that some victims had been trapped in collapsed buildings.

Although flooding is common in Nigeria during the rainy season, meteorologists say this year's rains have been particularly heavy.

Last year, about 500,000 people were displaced nationwide.