At least 44 refugees including 20 children died after three separate boats carrying them capsized off the Greek islands of Kalymnos and Farmakonisi early on Friday.
Greek coastguards said they rescued 74 refugees near these islands following the crashing of the wooden boats into rocks shortly after midnight.
They reportedly recovered the bodies of 17 children, 17 women and 10 men.
An official earlier said, "They were on a wooden sailboat. We do not yet have a clear picture of how many were on board."
A search and rescue operation was ongoing off Kalymnos, a small island in the southeastern Aegean Sea, assisted by a helicopter and other vessels, he added.
The Turkish coastguard said they had found the bodies of three children on Friday after a third boat sank near the seaside resort of Didim.
In the past year, hundreds of thousands of refugees seeking a better life, mainly Syrians fleeing war, have risked their lives crossing the Aegean in an attempt to reach European Union countries.
At least 113 refugees have died in the Aegean already this year, according to the International Organisation for Migration.