At least 24 migrants have died off the Turkish coast trying to reach the Greek island of Lesbos, Turkish media say.
The victims, including children, drowned when their boat capsized after setting off from the Altinoluk area of Balikesir province.
About 400 people have died crossing into Europe in 2016, the International Organization for Migration (IOM) says.
Most were travelling to Greece. Recent fighting in Syria has sent thousands fleeing towards the Turkish border.
The sea route from Turkey to Greece was the most popular way for migrants to try and enter Europe in 2015.
In the latest incident, the boat capsized two miles into the crossing, Hurriyet newspaper said.
It denied earlier media reports that another migrant boat had capsized further south in Izmir province.
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 Mrs 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.
After her talks in Ankara, Mrs Merkel said: “In the past days we have been not only shocked but horrified by the human suffering of tens of thousands of people through bomb attacks predominantly carried out by the Russian side.”
Mr Davutoglu said his country would accept the migrants “when necessary”, and that it would reveal plans next week to slow the flow of arrivals.