SAO PAULO (AP) - Brazilian emergency officials say a rain-swollen reservoir overflowed a dam in the country's flood-stricken north, forcing 500 people from their houses.

Piaui state Civil Defense says in a statement that officials worry the Algodoes I dam could be in danger of collapsing.

It was not immediately clear Friday whether officials were releasing water to relieve pressure.

Heavy rains and devastating floods have been punishing northern Brazil for weeks.

The federal government says more than 313,000 people have been left homeless in 11 states, an area three times the size of Alaska. Thirty-nine people have died.

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