Libya's coastguard on Saturday rescued 89 sub-Saharan African migrants who had been drifting in a boat for five days and who had to dump the bodies of five people who died on the journey overboard, the state news agency said.

The Libyan authorities were alerted by a fisherman that the boat was adrift off the western port of Zawiyah, naval official Colonel Ayub Omar Gacem was quoted as saying by the Libyan news agency LANA.

"Many of them were taken to hospital when they were brought to shore, the rest were provided with food and medicine on the spot," Ayoub was quoted as saying.

The migrants told their rescuers that five people had died and they had disposed of their bodies at sea.

North Africa is a launch point for maritime migration to southern Europe, with Italy the main destination. Thousands of people have been killed attempting the dangerous crossing in overcrowded and frequently unsafe vessels.

Ayoub said this was the second such incident in two weeks after Libya's coastguard saved another 34 people, including women and children, off the west coast.

On Friday, the Italian coastguard said it had rescued almost 500 migrants crammed into five small inflatable boats off the Sicilian coast in the Mediterranean Sea after receiving distress calls overnight.

Most of the migrants were taken to Lampedusa, a tiny island south of Sicily that receives thousands of immigrants each year.

Improved spring weather conditions have increased the numbers trying to make the treacherous journey across the Mediterranean, but thousands have died due to shipwrecks, harsh conditions and a lack of food and water.

An estimated 1,500 migrants lost their lives in the Mediterranean in 2011, many of them trying to escape the turmoil caused by the Arab Spring uprisings in North Africa, according to Human Rights Watch. It estimated the death toll in 2012 at more than 300.