ISTANBUL - Turkish police on Wednesday detained at least five suspected Islamic State group militants believed to be linked to the deadly
Istanbul nightclub attack, the state-run news agency reported.

The operation was launched in the Aegean port city of Izmir and was ongoing, Anadolu Agency said.

The private Dogan news agency said the police operation targeted three families who had arrived in Izmir about 20 days ago from Konya -- a city in central Turkey where the gunman is thought to have been based before carrying out the nightclub attack. It said 27 people, including women and children, were taken into custody.

At least 14 people were previously detained in connection with the attack, including two foreigners stopped Tuesday at the international terminal of Istanbul's Ataturk Airport after police checked their cellphones and luggage, according to Anadolu.