As the search for thousands of missing people continues in the Libyan city of Derna after massive flooding, the United Nations said the scale of the disaster was still unknown.

The flow of water last Sunday evening led to the collapse of two dams in areas above Derna, causing the river - which crosses the city - to flood lightly, according to residents, explaining that the water flowed several meters high, and all bridges linking the east of Derna to its west collapsed.

An AFP photographer at the site said Derna city centre was like flat ground after trees were uprooted and buildings and bridges washed away.

Authorities fear the human toll will be heavy, with massive losses in the city, which had a hundred thousand people before the disaster.

With difficult access, communications and relief operations and the chaos prevailing in Libya even before the disaster, figures for the number of casualties are conflicting, and ministers in Libya's eastern government have given mismatched figures.

A spokesman for the interior ministry in the eastern government said on Wednesday that more than 3800,<> people died in the floods, while thousands were missing.


Witnesses

Residents say hundreds of bodies are still buried under tons of mud and rubble.

Abdelaziz Bousmiya, a 29-year-old resident of Derna's Shiha neighbourhood who survived the floods, told AFP: "The water was carrying mud, trees and iron debris and crossed kilometres before it swept through the city centre and swept away or buried everything that was in its path."

"I lost friends and relatives, some of whom were buried under the mud, and some of whom were washed away by the waters to the sea," he said, estimating the death toll at 10% of the city's population.

The Libyan authorities did not take the necessary measures to remedy the disaster, he said, but only instructed residents to stay at home in anticipation of Storm Daniel, which hit Turkey, Bulgaria and Greece, before it arrived last Sunday in Libya.

The number of body bags distributed in the city reveals the scale of the tragedy, and the International Committee of the Red Cross alone reported securing six thousand.

"The water level suddenly rose within seconds," said another survivor who was injured, noting that he and his mother washed away when floods struck at night, before they could cling to an empty building and take shelter in it.

At the height of the second floor

According to the testimony published by the Benghazi Medical Center, the man, who has not been identified, said, "The water level rose until we reached the fourth floor, the water was as high as the second floor."

"We heard people screaming, I saw from the window cars and bodies washed away, the situation lasted like this for an hour or an hour and a half that seemed to us like a year," he said.

U.N. Assistant Secretary-General for Humanitarian Affairs Martin Griffiths said on Friday the scale of the disaster in Libya was still unknown.

"I think the problem for us is to coordinate our efforts with the government and with other authorities in the east of the country, and then to determine the scale of the disaster," Griffiths said at a news conference, adding, "We have not reached that yet, we do not know it," and that "the level of needs and the number of deaths is still unknown."

The U.N. Office for the Coordination of Humanitarian Affairs (OCHA) has appealed for more than $71 million to provide immediate assistance to some 250,<> people most affected by the floods caused by Storm Daniel, warning of a "catastrophic" situation.

After the destruction of many roads, "the municipality (Derna) urges the authorities to establish a sea corridor for urgent assistance and evacuations," the office said, estimating the number of people directly affected by the disaster at 884,<>.

Paramedics search for victims and bodies and citizens follow (Anadolu Agency)

Very violent

Jan Fredes, head of the ICRC delegation in Libya, said the disaster "was very violent", adding that "a seven-metre-high wave swept buildings and infrastructure into the sea", noting that there were "bodies tossed by the waves on the beach".

The United Nations, the United States, the European Union and much of the Middle East and North Africa have promised to send aid, and foreign ambulance teams have begun working for any possible survivors.

International Meteorological Organization (IMO) Secretary-General Petteri Taalas said on Thursday that if there had been better coordination, "warnings could have been issued, emergency management bodies would have been able to evacuate the population and we would have avoided most of the casualties".

Taalas told reporters in Geneva that years of conflict in Libya had "largely destroyed the meteorological network and information systems".