Outside help was only just starting to reach the coastal city on Tuesday, more than 36 hours after the disaster struck. The floods damaged or destroyed many access roads to the Derna.

More than 1,000 corpses were collected, including the at least 700 that have been buried so far, the health minister for eastern Libya said. Derna’s ambulance authority has put the current death toll at 2,300.

The destruction came to Derna and other parts of eastern Libya on Sunday night. As the storm pounded the coast, Derna residents said they heard loud explosions and realised that dams outside the city had collapsed. Flash floods were unleashed down Wadi Derna, a river running from the mountains through the city and into the sea.

The Tripoli-based government of western Libya sent a plane with 14 tons of medical supplies and health workers to Benghazi. It also said it had allocated the equivalent of $412m for reconstruction in Derna and other eastern towns. Aeroplanes arrived Tuesday in Benghazi carrying humanitarian aid and rescue teams from Egypt, Turkey and the United Arab Emirates.

It was not clear how quickly the aid could be moved to Derna, 250km (155 miles) east of Benghazi, given conditions on the ground. Ahmed Amdourd, a Derna municipal official, called for a sea corridor to deliver aid and equipment.

The storm hit other areas in eastern Libya, including the town of Bayda. The Medical Center of Bayda, the main hospital, was flooded and patients had to be evacuated, according to footage shared by the centre on Facebook.

Other towns that suffered included Susa, al-Marj and Shahatt, according to the government. Hundreds of families were displaced and took shelter in schools and other government buildings in Benghazi and elsewhere in eastern Libya.