Turkish authorities say two suicide bombers detonated their explosives outside the capital, Ankara, after police ordered them to surrender.
Governor Erkan Topaca said both bombers, a man and a woman, were killed in the October 8 attack but no one else was injured.
The state-run Anadolu news agency said the suspects were preparing to commit a car-bombing.
Topaca suggested the attackers were connected to the banned Kurdistan Workers Party (PKK), a militant group blamed for a number of recent deadly car bombings.
Since the collapse last summer of a 2 1/2-year cease-fire between Turkey and the PKK, more than 600 Turkish security personnel and thousands of PKK fighters have been killed.
Turkey has also been the target of deadly attacks blamed on radical militants from Islamic State (IS), which controls territory in neighboring Syria.