ISTANBUL (AP) — As Turkey continues to investigate the Istanbul airport bombing and track down suspects, a Turkish official says the mastermind of an earlier suicide bombing has been killed.

The official said Friday Mehmet Sirin Kaya was killed by security forces in the town of Lice in the mainly Kurdish province of Diyarbakir.

The Feb. 17 suicide attack against military personnel in Ankara killed 29 people and was claimed by an offshoot of the Kurdistan Worker's Party, or PKK, which Turkey considers a terrorist organization.

The official spoke on condition of anonymity in line with government protocol.

Turkey is still reeling from the triple suicide bombing attack at Istanbul's Ataturk Airport earlier this week that killed 44 people. The Islamic State group is the main suspect for that attack.