Fourteen people died and a further 27 were rescued by Turkish authorities after their boat sank on its way to the Greek island of Lesbos, Dogan news agency reported on Wednesday.
Tens of thousands of migrants have made the perilous journey from Turkey to Europe in recent months, many of them fleeing conflicts in the Middle East while others came from Africa. The onset of winter has so far done little to stem the flow.
Children were among those who died when the wooden boat went down in the 8km (5 mile) stretch of water separating Lesbos from the Turkish coast, Dogan reported. Turkey's coastguard was not immediately available to comment.
European and African leaders are meeting on Wednesday in Malta to discuss the migrant issue, with the EU hoping that pledges of cash to some of the world's poorest countries will help discourage others from making the journey.
The European Union expects a battle at the summit of world leaders in Turkey on Sunday to have its migration crisis recognized as a global problem needing a global response, an EU official said on Tuesday.
Approximately 125,000 refugees arrived in Lesbos from Turkey in October, double the number in August, according to the International Rescue Committee (IRC). They are escaping wars and violence in Syria, Afghanistan, Iraq, Eritrea and elsewhere. More than 791,000 have arrived by sea since January.
What sets this humanitarian crisis apart is the centrality of volunteers. On Lesbos alone, they number well into the hundreds. They are lifeguards from Spain, doctors from Holland, trauma counselors from the West Bank, nurses from Australia, a cook from Malaysia, and all manner of ordinary people pitching in however they can.
Many come on their own dime, taking time off from work or pausing their lives indefinitely. They fill in critical gaps created by a perfect storm of political weakness and limits to aid: a Greek government in severe economic distress and without capacity to take control; a European Union strangled by politics as it struggles to define a uniform migration policy; and international aid groups that have been slow to move in because they do not normally operate in industrialized nations — and have to start their operations from scratch in a place like Lesbos.