Turkey has retaliated by bombing sites in northern Iraq used by the PKK, which it says carried out the attack
At least 28 people were killed and 61 wounded in a car bomb targeting the Turkish military in the capital Ankara on Wednesday, the city's governor said.
World leaders have condemned the attack, pledging to support the Turkish government in efforts to bring the perpetrators to justice and boost security.
Hours after Wednesday night's attack, the Turkish army retaliated by bombing sites controlled by the PKK in northern Iraq, killing around 70 of the group's members including several leaders.
The PYD denied responsibility for the attack, with its leader Saleh Muslim telling Sky News Arabia that his group has "no connection" to Wednesday night's bombing.
Wednesday night's bombing was aimed at a convoy of military service vehicles, Ankara governor Mehmet Kiliclar said, quoted by the CNN-Turk and NTV channels.
Plumes of smoke were seen rising over an area and the powerful blast was heard all over the city, sending residents to their balconies in panic, an AFP correspondent said.