Two boats on their way to Greece have capsized near Turkey, killing at least 35 migrants, Turkish media say.
Both the Anadolu and Dogan agencies reported that 24 people died close to the Greek island of Lesbos.
Dogan said another 11 people died in a separate incident further south, near Dikili in Turkey’s Izmir province.
Up to 5 February, at least 374 people had died crossing into Europe this year, the International Organization for Migration (IOM) says.
Most of those were travelling to Greece. The sea route from Turkey to Greece was the most popular way for migrants to try and enter Europe in 2015.
Dogan reported that a number of children were on board the boat on which the 24 people died. At least four people were rescued, Hurriyet newspaper said.
News of the deaths comes as Germany’s Chancellor Angela Merkel is in Turkey to discuss ways of reducing the number of migrants travelling to Europe.
After meeting Merkel, Turkish Prime Minister Ahmet Davutoglu said Germany and Turkey would seek the use of Nato resources in the Aegean Sea and on the Syrian border to help handle the flow of migrants.
The IOM says close to 69,000 people have already arrived on Greek shores so far this year, despite often stormy conditions, compared to almost 854,000 in the whole of last year.
Nearly half of those who have arrived in Greece this year are from Syria, the IOM says.
But thousands of Syrians seeking to flee a government offensive in Aleppo, backed by Russian air strikes, are being prevented from leaving their homeland.
Turkey has so far closed the border to most of the 30,000 migrants gathering at the Kilis border crossing, despite appeals by EU leaders to let them cross.
Davutoglu said his country would accept the migrants “when necessary”, and that it would reveal plans next week to slow the flow of arrivals.