Blast hits police building in Cizre, in south-east Turkey, killing nine policemen and injuring more than 45
The explosion occurred at 07:00 (04:00 GMT). Pictures show a multi-storey building in ruins, Unian reports.
It is unclear who carried out the attack, but Turkish media blamed the banned Kurdistan Workers Party, PKK.
Cizre has been the subject of several curfews in the past few months by Turkish authorities fighting the PKK.
A string of PKK attacks have targeted Turkish security forces since a two-year ceasefire collapsed in July 2015.
Since then, south-east Turkey has seen its worst violence in 20 years.
The latest violence comes as the army reels from a huge purge following a coup attempt in July.
As well as fighting the PKK, Turkey is battling so-called Islamic State, whose militants have carried out a series of bloody attacks over the past year.
The PKK, which is banned in Turkey, launched its insurgency in 1984, alleging widespread abuse and discrimination against Kurds by Turkish authorities.
Since the ceasefire broke down, military operations in the south-east and retaliatory attacks by the PKK have left hundreds of people dead.