Thirty-four refugees, almost half of them babies and children, drowned when their boat sank off a Greek island on Sunday, almost certainly the largest death toll in those waters since the migrant crisis began, the coastguard said.
Four babies, six boys and five girls died when the wooden vessel carrying them overturned on Sunday morning, about three miles (5 km) east of the small island of Farmakonisi, close to Turkey's coast, the service added.
Tens of thousands of mainly Syrian refugees have braved rough seas this year to make the short but precarious journey from Turkey to Greece's eastern islands, mainly in flimsy and overcrowded inflatable dinghies.
Thousands have died, many of them taking the much longer crossing from Libya, in Europe's worst migrant crisis in decades.
Details of the nationalities and ages of the victims of Sunday's sinking off Farmakonisi were not immediately available.
The coastguard said 68 people were rescued from the water and another 30 survivors from the same boat were found on Farmakonisi.