ATHENS, Greece (AP) — Two men found alive among 17 dead bodies in a partially sunken migrant boat south of the island of Crete over the weekend told Greek authorities the vessel had been carrying a total of 34 people, and that 15 had fallen overboard and were missing, Greece’s coast guard said Monday.

A search and rescue operation was underway, the coast guard said, but strong winds and rough seas have been hampering efforts.

On Saturday, the coast guard said a passing Turkish merchant vessel had come across the half-sunken migrant boat 36 nautical miles (41 miles, 66 kilometers) southwest of the town of Ierapetra in southern Crete. Seventeen of the passengers on board, all men, were already dead, and there were only two survivors, the coast guard said, revising its initial count of 18 bodies.

The survivors, both from Egypt, were transported to a hospital in Crete, and the bodies were taken to a morgue on the island for autopsies, the coast guard said.

The survivors later told authorities there had been a total of 34 people from Egypt, South Sudan and Sudan on board the vessel, which had set sail from Tobruk in Libya on the night of Dec. 1. The boat suffered engine failure the following day and began to drift. Fifteen of those on board fell into the water and went missing, authorities said.

Separately, the coast guard said the body of a boy was found along with 37 survivors from Syria and Afghanistan who had been transported to the eastern Aegean island of Samos on board a migrant smuggling speedboat Monday. The speedboat was later found run aground in a nearby cove, while the smuggler evaded capture, the coast guard said.

Greece is a major entry point into the European Union for people fleeing conflict and poverty in the Middle East, Africa and Asia. Fatal accidents are a common occurrence. The preferred route used to be the short but often perilous crossing from the Turkish coast to nearby Greek islands. But increased patrols and allegations of pushbacks — summary deportations without allowing for asylum applications — by Greek authorities reduced crossing attempts.

Instead, many migrants are undertaking the much longer sea crossing across the Mediterranean from North Africa, particularly from Libya, using roughly made wooden boats, large inflatable dinghies or old dilapidated fishing vessels.