According to the local officials, dozens of migrants are missing after a rubber boat they were on sank off the coast of Libya.
One official is quoted as saying 63 migrants have disappeared after Sunday's incident east of Tripoli, while 41 people have been rescued.
Since Friday, about 170 migrants have gone missing in the Mediterranean Sea.
The International Organization for Migration (IOM) said that smugglers are exploiting migrants desperate to get to the EU before it tightens its borders.
"There is an alarming increase in deaths at sea off Libya's coast," IOM's Libya Chief of Mission Othman Belbeisi said.