Turkish authorities say a man who carried out a suicide bomb attack against a local governor in southeastern Turkey was an Iranian national.
The governor was unhurt but his driver and the attacker were killed in the explosion on Thursday in the mainly Kurdish province of Bingol.
The authorities said two other Iranians and two Turkish nationals had also been detained.
The attack is the latest in a series since the arrest of the Kurdish separatist leader, Abdullah Ocalan, in February.
The security forces have arrested about 400 members of radical Islamic groups in the southeast of the country over the past month.
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