A car bombing targeted a police unit on Tuesday in Diyarbakir, a major city in south-eastern Turkey, killing three people and injuring 34, broadcaster CNN Turk reported.
The blast took place in the Baglar district of the largely Kurdish city and appeared to have hit a police transport bus.
Eleven police officers were among the injured.
Fighting between the state's security forces and Kurdish militants restarted last year after a two-year ceasefire broke down amid mutual recriminations between the government and the Kurdistan Workers' Party (PKK).
Militants have increasingly been using car bombs to attack security forces amid fighting taking place across numerous provinces in the mostly Kurdish south-east.