Police arrested three PKK terrorists in Turkey's Istanbul, Izmir and Çanakkale provinces, a statement released by Diyarbakır Governorate said Sunday.

The terrorists were detained as part of an investigation launched by the anti-terror branch of Diyarbakır Gendarmerie Forces, which determined that they were staying at cells in the three cities.

In the statement, the governorate in the southeastern Turkish province said that anti-terror teams of gendarmerie arrested three suspects identified as Hogir Van, Dersim Çewlik and Kendal Azadi and brought them to Diyarbakır.

The suspects reportedly joined the terrorist group in 2015.

They were plotting suicide attacks in metropolitan cities, the statement added.

Two of them were remanded in custody while the third one was released under judicial control, according to the statement.

In its more than 30-year terror campaign against Turkey, the PKK -- recognized as a terrorist group by Turkey, the U.S., and the EU -- has been responsible for the deaths of some 40,000 people, including women and children.