So far, five fatalities have been found and several people are being treated in hospital with serious injuries. 39 others have been rescued by ships that were in the vicinity and by the Greek coastguard and military. Several people who have been rescued have testified that at least 80 people were on board when the boat sank.
The accident occurred just south of the small island of Gavdos, which is located south of Crete, late on Friday.
In two other separate incidents off Gavdos on Saturday, 88 migrants were located and rescued by a tanker flying the British flag and 47 people by a cargo ship flying the Maltese flag, also south of the island.
At the end of November, eight migrants, including six minors, died north of the island of Samos, on a route often used by human smugglers.
Greece has seen a 25 percent increase in the number of arriving migrants this year – just to the holiday island of Rhodes, there has been a 30 percent increase, according to the migration department.