At least 11 people were wounded on Thursday in a bomb attack targeting the Turkish police in the Kurdish-majority southeastern city of Diyarbakir, hospital and security sources said.
Three of the injured in Diyarbakir were members of the security forces, the sources added.
Turkish forces are engaged in an operation against Kurdish rebels from the outlawed Kurdistan Workers Party (PKK) in the region.
Security sources told AFP the bomb exploded as a police armoured vehicle drove past.
The attack came as Prime Minister Ahmet Davutoglu, whose government has waged a relentless campaign against PKK rebels since last summer, was due on Friday to make a rare visit to Diyarbakir.
Hundreds of security forces members have been killed since the PKK resumed its more than three-decade insurgency after a fragile truce collapsed last summer.
President Recep Tayyip Erdogan said this week that 355 members of the security forces had been killed in the fighting, along with 5,359 members of the PKK. It was not possible to confirm the toll on the rebel side.