(CNN) —  

At least 17 people were killed when gunmen attacked gas pipeline workers about 50 miles northeast of Baquba, north of Baghdad, Iraqi police officials in Baquba said Friday.

Police said most of those killed and injured were Iranians working on a pipeline between Iran and Iraq. Gunman ambushed the workers with small arms fire, authorities said.

Police did not provide any more details regarding a motive or who might be responsible for the ambush.

Baquba is the capital of Iraq’s Diyala province, which borders Iran.

16 killed in Baghdad violence