Turkey has begun security operations against Kurdish rebels in the country's south-east and in Iraq.

The moves come as President Recep Tayyip Erdogan vowed a crackdown on terror after Sunday's attack in Ankara that killed at least 36 people.

A suspected bomber, who also died in the blast, was a female member of the PKK, security sources said.

Four people were held over the bombings in the south-eastern city of Sanliurfa, according to Turkish media.

Officials were quoted as saying the car used in the bombing was traced to a showroom there.

A curfew was declared in three towns in south-east Turkey, while warplanes struck PKK camps in Iraqi Kurdistan.

Eleven warplanes carried out air strikes on 18 targets including ammunition dumps and shelters in the Qandil and Gara sectors, the army said. The PKK (the outlawed Kurdistan Workers Party) confirmed the attacks.

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Meanwhile curfews have been imposed in two mainly Kurdish towns in south-eastern Turkey, Yuksekova and Nusaybin, as security operations are carried out against Kurdish militants, Anadolu news agency reports.

Another curfew is due to start in the city of Sirnak at 23:00 local time (21:00 GMT).

No group has admitted carrying out the attack in the capital, Ankara, but government sources have cast suspicion on the PKK.