Turkey’s prime minister says the deadly bombing in Ankara was carried out by Kurdish YPG militia based in Syria, and nine people have been arrested.
Ahmet Davutoglu said the fighters worked in co-operation with militants from the outlawed Kurdistan Workers Party (PKK) in Turkey.
Turkey carried out strikes on PKK forces in north Iraq late on Wednesday.
Meanwhile, a military convoy in south-east in Turkey has been hit by a bomb, killing at least six troops.
The blast happened on a highway between the towns of Diyarbakir and Bingol.
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Mr Davutoglu said 26 of the 28 people killed in the bombing of a military convoy in the capital Ankara on Wednesday were soldiers.
He named the Ankara bomber as Salih Necar, a Syrian national and member of the Syrian Kurdish People’s Protection Units (YPG).
“A direct link between the attack and the YPG has been established,” he said. He went on to say the attack was carried out with logistical support from PKK militants inside Turkey.
Turkey considers the YPG a terrorist group, but its allies, including the United States, back the YPG, in its fight against so-called Islamic State (IS).
Mr Davutolgu said the bombing in Ankara proved the YPG is a terrorist group, and said he expects co-operation from Turkey’s allies in tackling them.