More than 5,300 people were killed and at least 10,000 were missing in Libya in floods caused by a huge Mediterranean storm that burst dams, swept away buildings and wiped out as much as a quarter of the eastern coastal city of Derna.

Officials expected the death toll to rise further after Storm Daniel barrelled across the Mediterranean into a country divided and crumbling after more than a decade of conflict.

In Derna, a city of around 125,000 inhabitants, Reuters journalists saw wrecked neighbourhoods, their buildings washed out and cars flipped on their roofs in streets covered in mud and rubble left by a wide torrent after dams burst.

Mohamad al-Qabisi, director of the Wahda Hospital, said 1,700 people had died in one of the city's two districts and 500 had died in the other.

Bodies were lined up on the street outside a crowded hospital, with residents looking under the shrouds covering them in search of loved ones.

Similar devastation reigned on the way into Derna, with vehicles overturned on the edges of roads, trees knocked down and houses inundated and abandoned.

"Bodies are lying everywhere - in the sea, in the valleys, under the buildings," Hichem Abu Chkiouat, minister of civil aviation in the administration that controls the east, told Reuters by phone shortly after visiting Derna.

"I am not exaggerating when I say that 25% of the city has disappeared. Many, many buildings have collapsed."

Abu Chkiouat later told Al Jazeera that he expected the total number of dead across the country to reach more than 2,500, as the number of missing people was rising.

Other eastern cities including Libya's second biggest city Benghazi, were also hit by the storm. Tamer Ramadan, head of a delegation of the International Federation of the Red Cross and Red Crescent Societies, said the death toll would be "huge".

"We can confirm from our independent sources of information that the number of missing people is hitting 10,000 so far," he told reporters via video link.

United Nations aid chief Martin Griffiths said in a post on X, formerly known as Twitter, that emergency teams were now being mobilised to help on the ground.

As Turkey and other countries rushed aid to Libya, including search and rescue vehicles, rescue boats, generators and food, distraught Derna citizens rushed home in search of loved ones.