ROME - Hundreds of people and 16 dead bodies were pulled out of the sea near the tiny southern Italian island of Lampedusa on Sunday, highlighting the need for increased attention to the growing refugee crisis from war-torn North Africa and again bringing immigration issues to the forefront in Italy.

An overcrowded ship carrying up to 600 people trying to flee Libya sank on Friday just outside the port of Tripoli, UN High Commissioner for Refugees (UNHCR) spokeswoman Laura Boldrini said.

Aid officials were still trying to confirm the fate of those people and said that around 100 people were still unaccounted for.

The Italian media said at least 16 of them died, including two babies, but the death toll was likely to rise.

Witnesses who left the Libyan capital on another boat shortly afterward reported seeing remnants of the sunken ship and the bodies of some passengers floating in the sea.

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At least three other boats that left Libya in late March have disappeared, with hundreds feared dead, Boldrini said.

The number of people fleeing North Africa has soared since mid-January, after Tunisia overthrew its president and set off a series of uprisings in Egypt and Libya.

Some 25,000 people, mostly Tunisians, have flooded Lampedusa, which is right off the North African coast.

Since fighting began in Libya in mid-February, it is estimated that another 10,000 people have reached Lampedusa or the neighboring island of Linosa from Libya, including almost 2,000 who arrived on five boats last weekend.

Many of those fleeing Libya are foreign workers from sub-Sahara Africa.

Boldrini said the deaths and disappearances among people trying to cross the Mediterranean to flee unrest in Africa is increasing as smugglers begin to use bigger and less seaworthy boats.

"Most of the boats, if not all of the boats, are unseaworthy," said International Organization for Migration spokeswoman Jemini Pandya. "In addition, the boats are way overladen."

Witnesses of Friday's sinking said the Libyans "continued putting people onto the boat, way more than they should have", Pandya said.

In other missing boat cases, Boldrini said the UNHCR told the Italian coast guard that two boats carrying 120 and 360 migrants respectively left Libya in late March but never arrived in Italy. Their relatives fear they are dead since they have lost contact with them.

In a third case, relayed by an Eritrean priest in Rome to Boldrini, a boat with more than 70 people on-board ran into trouble in the Mediterranean and only a handful survived, making their way back to Libya.

London-based newspaper, the Guardian, reported on Monday that 61 African migrants died of hunger and thirst in March on that ship after being ignored by a NATO warship and helicopter, but NATO denied the accusation.

Aid officials said it was impossible to know how many people have drowned this year while trying to reach Europe.

"There's been no way of charting for sure how many boats have left, how many people never made it. Some of them we will never know about," said Pandya.

The topic of immigration was already one of the main topics of conversation in a summit between Italian Prime Minister Silvio Berlusconi and French counterpart Nicholas Sarkozy last month, and Italian officials have been calling for European Union aid to help process the thousands of illegal African immigrants coming ashore in Lampedusa, Sicily and elsewhere.

In another development, EU interior ministers will meet on Thursday to debate a raft of ideas to deal with a wave of migrants fleeing unrest in North Africa.

Xinhua-AP