Italian rescue vessels and a helicopter managed to pick up 48 people from the craft which had been carrying around 180 migrants which was found in heavy seas around 70 kilometres (40 miles) southwest of the Italian island of Lampedusa, the Coast Guard said in a statement.

The search and rescue effort is being hampered by the rough sea.

"We are still hoping. Our boats and helicopters have thrown all sorts of lifejackets and lifeboats to allow people to hold on," a coast guard official said.

Coast guards said in a statement that the boat was 13 metres long and had departed two days ago from the town of Zuwarah in western Libya. The statement said the people on the boat were mostly Eritreans and Somalis and included women and children.

Hundreds of African refugees from Libya—many of them migrant workers stranded after the start of an uprising against Libyan leader Muammar Gaddafi and the beginnings of a civil war -- have landed in Italy in recent days.

More than 20,000 migrants fleeing continuing unrest in Tunisia have also arrived on Lampedusa, sparking a humanitarian emergency. Migrants often travel in rickety and overcrowded fishing boats and there have already been smaller accidents at sea.

The tiny island of Lampedusa is closer to North African shores than to mainland Italy and Malta and has become a gateway for illegal immigration into Europe. Italian media reported that a coast guard vessel with those refugees rescued from the disaster was set to arrive on the outcrop imminently.

"They are not in serious condition but they need attention," the official said.

The accident happened some 40 nautical miles (46 miles, 74 kilometres) south of Lampedusa in waters that are under the jurisdiction of Malta. A fishing boat is also taking part in rescue efforts, the coast guard said.

DISTRESS SIGNAL RECEIVED IN MALTA AND LAMPEDUSA

A distress signal from the refugee boat was received overnight by Maltese authorities and officials in Lampedusa thanks to a satellite phone on board. Italy's coast guard said it had sent two vessels and a helicopter.

The boat was caught in high seas whipped up by strong winds and overturned after passengers panicked. Because of the storm and the panic on board, "the boat capsized and the passengers were thrown into the sea."

"The darkness and weather conditions made the search for the missing people difficult but it is still continuing," he said.

Appeals have gone out to ships in the area to aid the rescue operation.

Prime Minister Silvio Berlusconi hosted a government meeting to discuss immigration and the crisis in North Africa. Interior Minister Roberto Maroni, who struck a deal in Tunis yesterday to send back migrants arriving from Tunisia, was also present.

Italian media reported that the government could grant temporary residence permits to those Tunisian migrants who have already landed but will send back any new arrivals. "The darkness and weather conditions made the search for the missing people difficult but it is still continuing."

The Malta Rescue Centre is coordinating the search and the AFM has dispatched an Islander search aircraft.