DERNA, LIBYA -- People whose homes were swept away by flooding in Libya's eastern city of Derna a week ago faced the dilemma on Sunday of whether to stay and risk infection or flee through areas where landmines have been displaced by the torrents.

Thousands of people were killed after two dams above Derna broke on Sept. 10 during a powerful storm, bringing down residential blocks lining a usually dry river bed as people slept. Many bodies have been washed out to sea.

The UN's Office for the Coordination of Humanitarian Affairs (OCHA) said approximately 11,300 people had died - more than double the figure given by the International Organization for Migration on Friday.

Latest updates

  • Search for survivors goes on a week after disaster
  • Report warns of twin risks of water shortages and mines
  • UN agency reports death toll jump to 11,300
  • Volunteers from west of divided Libya bring aid to east

-----------------------------------------

The Libyan Red Crescent, which OCHA cited for the data, distanced itself from the report but OCHA stood by it.

More than 1,000 have already been buried in mass graves, according to the United Nations, and aid groups have warned against the practice. Libyan authorities have confirmed that 150 people have been poisoned by polluted water in the flood-hit areas.

Mohamed Wanis Tajouri said he had come to Derna from Benghazi down the coast with fellow medical students to carry out disinfection and sterilization work.

"After floods epidemics occur," he said.

Sunrise on Sunday revealed a scene of quiet devastation, with piles of rubble cleared to the sides of empty roads along with tangled metal including pieces of wrecked cars.

Hamad Awad sat on a blanket on an empty street with a bottle of water and bedding alongside him.

"I am staying in our area trying to clean it and trying to verify who is missing," he said. "Thank God for giving us patience."

Entire districts of Derna, with an estimated population of at least 120,000, were swept away or buried in mud. State media said at least 891 buildings had been destroyed in the city, whose mayor has said 20,000 people may have died.

Mohamed Alnaji Bushertila, a government employee, said 48 members of his wider family were missing. Another resident said survivors were at a loss over what to do next.

"We still do not know anything, we are hearing rumors, some are trying to reassure us, others are saying you need to leave the city or stay here. We have no water and no resources," said the man, who gave just one name, Wasfi.

OCHA said the homeless were surviving in makeshift shelters, schools or packed into the houses of relatives or friends.

Floodwaters had shifted landmines and other ordnance left over from years of conflict, posing an extra risk to the thousands of displaced people on the move, it said.

CLINGING ON

Aid organizations have flown in emergency aid and some countries have sent supplies, although international officials say much more help is needed. A French field hospital was being prepared in footage aired by Libya's Al Masar television.

"People came with aid from all over, and this made it easier on us, and we felt that we are not alone," said Derna resident Hassan Awad as civil protection workers from Algeria searched the rubble of multistorey buildings in the city for survivors.

Awad pointed to a rusty pole between two buildings and said clinging to it was how his family had survived the flood which tore through their home, covering everything in mud.

"We found dead bodies, of neighbors, friends and loved ones," he said. On the seafront, an excavator moved smashed furniture and cars to try to find victims underneath. Another excavator cleared rubble from buildings as rescue workers paused and knelt nearby to pray.

In al Badya, a coastal settlement west of Derna, the hospital was treating victims from Derna as well as its own. Doctors built makeshift dams in the street when the flooding hit to try to hold back the water, but it rose within the building.

"This affected machinery and the infrastructure of the lower level of the hospital," the hospital's head, Abdel Rahim Mazek, said.

Elsewhere in the town, volunteers handed out clothing and food.

"People left their houses with nothing, they didn't even have their underwear," said one of the initiative's supervisors, Mohammad Shaheen.

Volunteer Abdulnabi said the team came from Ajaylat, around 800 miles (1,200 kilometres) away in western Libya, divided from the east by more than a decade of on and off conflict.

"People are coming together to help those impacted," he said.

The country of 7 million people has lacked a strong central government since a NATO-backed uprising that toppled Muammar Gaddafi in 2011 and its oil wealth is dispersed among competing groups.

Analysts said the disaster had brought some coordination between the internationally-backed administration in Tripoli in the west and the rival administration in the east but that reconstruction efforts would likely reopen faultlines.

The OCHA report on Saturday said alongside 11,300 dead more than 10,000 people were missing in Derna after Storm Daniel swept over the Mediterranean and into the city and other coastal settlements.

A spokesman for the Libyan Red Crescent cited by the report referred Reuters to the authorities, saying "figures are changing and the Red Crescent is not responsible for this."

An official from the administration that runs eastern Libya, Dr. Osama Al-Fakhry said: "The number of dead so far is 3,252, and they are those who were buried."

OCHA spokesperson Eri Kaneko stood by its report, noting that the World Health Organisation had confirmed 3,922 deaths.

More than 40,000 people had been displaced, OCHA said, cautioning that the figure was likely much higher since access had been restricted to the worst-affected areas such as Derna.

(Additional reporting by Abdelaziz Boumzar, Ayman Sahly and Essam ElFatori in Derna, Michelle Nichols at the United Nations, Adam Makary, Thomas Perry and Maya Gebeily; writing by Philippa Fletcher; editing by Christina Fincher and Susan Fenton)