Five Afghans, including two children and a six-month old baby, have drowned trying to reach Greece as Turkey starts to implement an EU agreement to curb illegal migration.
The stream of migrants risking perilous sea crossings has so far shown little sign of abating after Turkey reached the draft deal with the EU on Monday, under which it will try to stem the flow in return for funding and political rewards.
Turkey's EU Minister Volkan Bozkir said the deal, under which Ankara agreed to take back all irregular migrants, does not apply to those who have already reached the Greek islands and that the number returned was ultimately expected to be thousands or tens of thousands.
One of the victims from Wednesday night's capsize, in which their boat hit rough weather as it travelled through the Aegean towards the Greek island of Lesbos, managed to swim ashore but died during attempts to revive him, a coastguard official told Reuters.
Of the four bodies found at sea, one was that of a six-month-old baby, rescuers said.
Nine other people were pulled from the water alive.
"The rescue operation for the two others is continuing," the coastguard official said.