According to Libya sources, at least 3,000 people are now believed to have died and another 10,000 still missing in the massive floods that have overwhelmed parts of eastern Libya.
The International Federation of the Red Cross and Red Crescent Societies (IFRC) official also said that around 10,000 people are thought to be missing.
“We can confirm from our independent sources of information that the number of missing people is hitting 10,000 so far,” said Tamer Ramadan, the head of the IFRC delegation in Libya.
Widespread flooding and mudslides caused by torrential rain have destroyed many roads and homes.
The worst-affected place is the port of Derna, much of which is under water after two dams and four bridges collapsed.
“The death toll is huge and might reach thousands,” added Mr Ramadan.
The IFRC could soon launch an appeal for emergency funding to support Libya’s flood victims.
On his part Libya’s Red Crescent spokesman Taqfiq Shukri said on Tuesday that there are 2,084 people confirmed dead.
Some 20,000 people have been displaced, according to estimates. Libya’s eastern administration, based in Benghazi, also estimates that 3,000 people are dead.
In the capital Tripoli, Government of National Unity Prime Minister Abdul Hamid Dbeibah announced on Tuesday that an aid plane carrying 14 tonnes of supplies and medical personnel is headed to Benghazi to help, although there are still difficulties entering the hardest-hit city of Derna.
Relief convoys are moving from west to east in divided Libya as the internationally recognised Tripoli government has declared the eastern region a disaster zone and announced it would be sending help.
The Benghazi administration says more than 1,000 bodies have been retrieved in the Mediterranean city of Derna.
On Monday, Storm Daniel swept eastern Libya, causing two dams on the Wadi Derna River to burst and send millions of cubic metres of water downstream to inundate the river plain, hitting Derna.
Apartment blocks partially collapsed, and a seafront bridge was washed away as tonnes of water rushed to the sea.
According report from Aljazeera, “Authorities have struggled to reach Derna, because roads leading to the city are destroyed or cut off by flooding.” However, aid has begun to reach people outside the city of Derna.