Five were among 11 Syrians killed after their plastic boat sank off Turkey's Aegean coast on Friday, the Dogan news agency said, the first such reported incident in months on an illegal migrant route meant to have been all but shut down.
Television footage showed rescue workers standing next to bodies washed up on a beach near the coastal town of Kusadasi. The boat, believed to have been carrying 22 Syrian migrants, had been heading for Greece.
A baby in a critical condition was among the 11 people rescued alive, Dogan quoted district governor Muammer Aksoy as saying. He said 11 bodies had been recovered.
Dogan earlier said the authorities had detained two Turks suspected of organizing the voyage after they swam ashore. The news agency initially said 12 people had been killed.
A between Turkey and the European Union on curbing illegal migration, struck a year ago, helped significantly reduce the migrant flow to Europe via the Greek islands. Some, however, are still trying to make the perilous voyage.
More than 3,620 refugees and migrants have crossed to Greece from Turkey so far this year, according to the United Nations refugee agency UNHCR, and about 60 arrive on Greek islands each day. At least 173,000 people, mostly Syrians, arrived in 2016.
Europe's deteriorating relations with Turkey could endanger the migrant deal, under which Ankara is supposed to help control migration in return for the promise of accelerated EU membership talks and aid.
President Tayyip Erdogan, who accuses Brussels of failing to keep its promises, said on Thursday that Turkey would review all political and administrative ties with the EU after an April referendum, including the migrant deal.
Erdogan has been angered by Germany and the Netherlands cancelling planned rallies on their territory by Turkish officials seeking to drum up support for a "yes" vote in the referendum, which is on constitutional changes that would extend the powers of the presidency.