More than 30 migrants died and 200 were rescued on Saturday after their boats foundered off Libya's western coast, the Libyan navy said.

The coastguard conducted two rescue operations off the city of Garabulli, 60 kilometers (40 miles) east of Tripoli, spokesman Colonel Abu Ajila Abdelbarri said.

He added that patrols had found 31 bodies and 60 survivors from one boat, along with a further 140 survivors from a second.

"When we arrived at the spot, we found an inflatable dinghy with several people clinging to part of it," he said.

He did not specify whether any migrants were missing.

"The weather conditions these days are favorable for sending migrants to European shores on boats that are often unseaworthy," he added.

Libyan patrol boat commander Nasser al-Ghammoudi said one of the migrants' vessels was three-quarters under water when the coastguard arrived.

"We looked for other survivors for more than five hours," he said. "We were able to rescue one woman after we heard her shouts."

The survivors were brought back to a naval base in Tripoli where the authorities provided them with water, food and medical care.

Migrants intercepted or rescued by the Libyan coastguard are usually held in detention centers to await repatriation, but waiting times are often long and conditions deplorable.

Libya is the main departure point for mostly African migrants trying to cross to Europe. Smugglers usually pack them into flimsy inflatable boats that often break down or sink.

Most migrants are picked up by international vessels and taken to Italy, where more than 115,000 have landed so far this year, although an increasing number are intercepted by Libya's European-backed coastguard and returned to the North African country.

Since July, there has been a sharp drop in crossings, though this week has seen a renewed surge in departures.

Nearly 3,000 migrants are known to have died or be missing after trying to cross to Europe by sea this year, the majority of them between Libya and Italy. The International Organization for Migration said on Friday that since 2000 the Mediterranean had been "by far the world's deadliest border".