At least 60 migrants, most of them Palestinian and more than half of them children, died after their overcrowded boat sank just tens of metres off Turkey's western Aegean coast.
Local governor Tahsin Kurtbeyoglu said an initial investigation showed the small vessel sank due to overcrowding around dawn.
Its destination was unclear but the small Turkish town of Ahmetbeyli from where it left is only a few kilometres from the Greek island of Samos.
Greece is a common entry point for migrants trying to get into the European Union.
"The latest death toll we have is 60 people, including 11 men, 18 women and 31 children, including three babies," Mr Kurtbeyoglu said from the city of Menderes in Izmir province.
Turkish media said the reason the death toll was so high was because the women and children were in a locked compartment in the lower section of the vessel, although there was no official confirmation of this.
Mr Kurtbeyoglu said 46 people had so far been rescued alive, including the ship's Turkish captain and assistant, who had been placed under arrest.
He said there were no bodies left on the boat and he did not expect the death toll to rise any further.
Most of the migrants were Palestinian nationals and the authorities are still trying to determine the nationality of the others.
Mr Kurtbeyoglu the survivors spoke Arabic and were of Middle Eastern origin.
Turkish media said there were also Syrians and Iraqis on the boat, although that could also not be confirmed.
Turkey is catering for about 80,000 Syrian refugees near its southeastern border with Syria, several hundred kilometres away on the other side of the country.