A migrant boat carrying 45 people sank off southwest Turkey, prompting the coast guard to launch a search and rescue mission, the Turkish defence ministry said Friday.
The coast guard was searching for the missing boat "after receiving a tip-off" that it sank on Thursday some 260 kilometres (160 miles) off the coast of the holiday resort town of Kas, the ministry said in a statement.
There was no immediate information on the nationalities of the migrants.
Illegal immigrants often use Turkey as a gateway to reach prosperous European Union states, mainly via Greece.
Many rely on smugglers and risk their lives through perilous journeys in overcrowded boats.
In 2016, Turkey inked a deal with the EU to stem the flow of migrants to Europe.