Italian rescuers are still searching for some 40 missing people after a boat packed with illegal immigrants sank off southern Italy, killing at least 10.
Italy wants international help to stem the flow of migrants
An Italian navy ship spotted the vessel before it began to list, and was able to rescue about 70 people.
The 10m (33ft) long migrant boat sank before dawn on Saturday in a relatively calm sea, about 15km (10 miles) off the remote Italian island of Lampedusa.
Survivors said it sank when people saw the navy ship and rushed to one side.
The AFP news agency says Sicilian investigators are also probing the possibility that the Italian ship may have caused the boat to sink as it manoeuvred during the rescue attempt.
Survivors estimated there were up to 120 people aboard the boat.
Coast guard vessels and helicopters later joined the operation.
Police are questioning five survivors suspected of involvement in people trafficking.
Lampedusa has become a magnet for migrants hoping to reach Europe from North Africa.
Many Africans attempt the journey, often on overcrowded and unsafe boats.
The Italian interior ministry said 178 boats with a total of 10,414 people on board arrived on Lampedusa between 1 January and 31 July this year, compared with 6,901 illegal immigrants during the same period in 2005, AFP reported.
Meanwhile, the Spanish authorities say more than 800 would-be illegal immigrants have arrived in the Canary Islands in boats from Africa in the past two days.
Another boat has been spotted offshore.
On Friday the regional government in the Canary Islands renewed calls for the authorities in Madrid to take urgent action over what it termed a human avalanche.
More than 17,000 illegal migrants have made it to the Canaries from the African mainland so far this year - three times last year's total. Many others have died in the attempt.