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.

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.

Mahmut Demirtas, the provincial governor of Adana, said a police official and four bystanders were slightly injured by a bomb that targeted a bus carrying police personnel.

“As of now, two chief prosecutors of the terror bureau have been assigned and they too are at the crime scene at the moment,” Demirtas said.

“According to initial reports, we are considering the possibility of a terror attack,” he added.

Demirtas said that either an improvised explosive device or a different kind of bomb may have been used in the attack in the central Yuregir district.