DERNA : Libyan authorities have opened an investigation into the collapse of two dams that caused a devastating flood in a coastal city as rescue teams searched for bodies on Saturday, nearly a week after the deluge killed more than 11,000 people.Heavy rains caused by Mediterranean storm Daniel caused deadly flooding across eastern Libya last weekend.The floods overwhelmed two dams, sending a wall of water several metres (yards) high through the centre of Derna, destroying entire neighbourhoods and sweeping people out to sea.More than 10,000 are missing, according to the Libyan Red Crescent. Six days on, searchers are still digging through mud and hollowed-out buildings, looking for bodies and possible survivors. “I found the kid in the water next to his grandfather,” said Ayoub, who only gave his first name. Tens of thousands of people have been displaced in the region and took shelter in schools and other government buildings.Dozens of foreigners were among those killed, including people who had fled war and unrest elsewhere in the region.Others had come to Libya to work or were travelling through in hopes of migrating to Europe. At least 74 men from one village in Egypt perished in the flood, as well as dozens of people who had travelled to Libya from war-torn Syria.