According to survivors, the migrants were stranded at sea after traffickers stole their boat's motor. If confirmed, the deaths will bring the number of migrants killed in the Mediterranean to nearly 2,000 this year.
As many as 126 migrants are feared dead after their boat sank off the coast of Libya last week, the UN's migration office said on Monday.
According to four survivors who were brought to the Sicilian port of Palermo after being rescued over the weekend, the shipwreck may have caused the death of 126 migrants, International Organization for Migration (IOM) spokesperson Flavio Di Giacomo said.
The survivors - two Sudanese and two Nigerians - said traffickers stole the boat engine several hours after they left the Libyan coast on Thursday.
"They stole the motor - something which has happened a few times recently - and at that point the boat started to take on water and sank," Di Giacomo said.
The four survivors were then picked up by a Libyan fishing boat and handed over to another migrant boat, which was later intercepted by the Italian navy and brought to Sicily.
More than 2,200 migrants were rescued from rickety boats by the Italian Navy, private charity boats and international military ships in the Mediterranean this weekend, IOM said.
Since the beginning of the year, more than 77,000 migrants have crossed the Mediterranean, with nearly 66,000 of them arriving in Italy. More than 1,800 migrants have perished at sea.
cw/tj (AFP, AP, dpa, Reuters)