A bomb has gone off in the mainly Kurdish city of Diyarbakir in the south-eastern region of Turkey.
The blast ripped through a compound of the riot police headquarters - specifically a vehicle repair bay - in a residential section of the city.
A police source told Reuters the explosion caused part of the roof to collapse, and one person is said to be in a critical condition.
Pictures on social media showed a large plume of smoke rising over buildings in the district.
The city is at the heart of tension between Kurdish dissidents and the Turkish government, and this incident comes mere days before a referendum on whether or not President Recep Tayyip Erdogan's powers will be increased under a constitutional reform.