Fifteen people, many of them children, drowned and thousands were displaced when overnight rain caused flash flooding in the southern Philippines, an army spokesman and disaster agency officials said on Wednesday. A dozen people were unaccounted after rivers in Davao City overflowed and flooded residential areas, said Benito Ramos, executive director of National Disaster Risk Reduction and Management Council (NDRRMC). "People in five villages were caught by surprise when the floodwaters rose up to 10 feet deep while most of them were sleeping on Tuesday," Ramos said, adding about 10,000 families moved to higher grounds. Reuters quoted Ramos as saying that the flood has subsided on Wednesday and emergency workers found bodies near a river bank. Army spokesman, Lieutenant-Colonel Leopoldo Galon, said seven children under 10 were among the 15 dead. Mayor Sara Duterte told reporters it was the first time the city had been hit by such flooding.