A bomb attack hit a bus carrying police in the southern Turkish province of Adana on Wednesday morning and some people were wounded, security sources said.
The blast in Adana was either an "improvised explosive device or a different type of bomb," the governor, Mahmut Demirtas, told Anadolu news agency.
One of those hurt was a police officer, he said, but the casualties did not suffer serious injuries.
The other four injured were passers-by, Demirtas added.
"The injured are in a really good condition. Citizens went to the hospital as a precaution. There are no issues for our police," Demirtas said after police and ambulance services rushed to the scene.
Images in Turkish media showed the damaged bus underneath a footbridge in Yuregir district.
The Adana governor did not speculate on who carried out the bombing.
Turkey was hit by a series of terror attacks in 2015 and 2016 which killed hundreds of people and were blamed on the Islamic State extremist group and Kurdish militants.
CNN Turk broadcast video of a badly damaged bus surrounded by debris and other damaged vehicles under a pedestrian overpass in the area of Yuregir in Adana.
The sources said ambulances took the wounded to hospitals in the area. Armed police sealed off the area and were examining the scene. It was not clear who might be behind the attack.