Two suicide bombers detonated explosives, killing themselves in a remote area near the Turkish capital, Ankara, on Saturday after police called on them to surrender, CNN Turk and other broadcasters reported.
The militants, believed to be a male and female, were suspected of being linked to the armed Kurdistan Workers Party (PKK) group and were believed to have been in possession of plastic explosives and 200 kg (440 pounds) of ammonium nitrate, CNN Turk said.
It said a third person was being sought.
The state-run Anadolu Agency said the two militants were preparing to carry out a car bomb attack when the blast occurred in countryside on the road from Ankara to the town of Haymana.
The PKK has fought a three-decade-old insurgency, focused in mainly Kurdish southeast Turkey, in which more than 40,000 people have been killed. It is designated a terrorist group by Turkey, the United States and European Union.
Leftist and Islamists militants have also carried out bombings in Turkey in the past, with the Islamic State militant group blamed for some recent attacks.