Philippine authorities on Tuesday began burying the dead from flash floods that have left more than 1,000 dead or missing, as President Benigno Aquino declared a national disaster.

Mr. Aquino flew to Mindanao island to inspect the ports of Cagayan de Oro and Iligan — choked with drying mud, crumpled homes, and hundreds of decomposing corpses after being struck by tropical storm Washi on the weekend.