DERNA, LIBYA - 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 the Mediterranean storm Daniel caused deadly flooding across eastern Libya last weekend.

The floods overwhelmed two dams, sending a wall of water several metres high through the centre of Derna, destroying entire neighbourhoods and sweeping people out to sea. More than 10,000 are thought to be 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.

The Red Crescent has confirmed 11,300 deaths so far. Claire Nicolet, who heads the emergencies department of the Doctors Without Borders aid group, said rescuers found “a lot of bodies” on Friday and were still searching.

“It was a big number ... the sea is still ejecting lots of dead bodies unfortunately,” she told The Associated Press.

She said massive aid efforts were still needed, including urgent psychological support for those who lost their families.

She said the burial of bodies is still a significant challenge, despite some progress in coordinating search and rescue efforts and the distribution of aid.

Authorities and aid groups have voiced concern about the spread of waterborne diseases and shifting of explosive ordnance from Libya‘s recent conflicts.

Haider al-Saeih, head of Libya‘s centre for combating diseases, said in televised comments Saturday that at least 150 people had suffered from diarrhoea after drinking contaminated water in Derna.

He urged residents to only drink bottled water, which is being shipped in as part of relief efforts.

Libya‘s General Prosecutor, al-Sediq al-Sour, said prosecutors would investigate the collapse of the two dams, which were built in the 1970s, as well as the allocation of maintenance funds.

He said prosecutors would investigate local authorities in the city, as well as previous governments.

“I reassure citizens that whoever made mistakes or negligence, prosecutors will certainly take firm measures, file a criminal case against him and send him to trial,” he told a news conference in Derna late Friday.

Local and international rescue teams were working around the clock, searching for bodies and potential survivors in the city of 90,000 people.

Ayoub said his father and nephew died in Derna on Monday, a day after the family had fled flooding in the nearby town of Bayda.

He said his mother and sister raced upstairs to the roof but the others didn’t make it. “I found the kid in the water next to his grandfather,” said Ayoub, who only gave his first name. “I am wandering around and I still don’t believe what happened.”

Al-Sour, the top prosecutor, called on residents who have missing relatives to report to a forensic committee that works on documenting and identifying retrieved bodies.

“We ask citizens to cooperate and quickly proceed to the committee’s headquarters so that we can finish the work as quickly as possible,” he said.

Libyan authorities have restricted access to the flooded city to make it easier for searchers to dig through the mud and hollowed-out buildings for the more than 10,000 people still missing.

Many bodies were believed to have been buried under rubble or swept out into the Mediterranean Sea, they said.

The storm hit other areas in eastern Libya, including the towns of Bayda, Susa, Marj and Shahatt.

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 traveling 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.