A number of people are reported to have been killed in an explosion in the largest city in Turkey's mainly Kurdish south-east region.
Justice minister Bekir Bozdag said both police and civilians are among the dead, but he did not say how many had been killed.
The blast happened in the Baglar district of Diyarbakir, near a building used by riot police.
Media reports said the explosion could be heard from several parts of the city and caused damage to nearby buildings.
Television footage showed people walking amid broken glass and other debris from a building where windows were blown out.
The Diyarbakir governor's office said the blast is believed to have been caused by a car bomb carried out by the rebels of the outlawed Kurdistan Workers' Party, or PKK.
It came hours after authorities detained at least 12 pro-Kurdish legislators for questioning in terror-related probes.
The private Dogan news agency reported that as many as 30 people were hurt in the blast.
Turkey has been plagued by a series of deadly bomb attacks in the past 18 months, carried out by Kurdish militants or Islamic State group extremists.