Gunmen ambushed a joint Iraqi army and police patrol near a town in the volatile Diyala province Tuesday, killing four security members and wounded six others, provincial police source said.

"Gunmen attacked a joint Iraqi army and police patrol with machine-guns and rocket propelled grenades, near the town of Khalis, 75 km northeast of Baghdad," the source told Xinhua on condition of anonymity.

The attack damaged several military vehicles, killed four security members and wounded six others aboard, the source added.

Diyala province, which stretches from Baghdad to the Iranian border to the east, has long been the hotbed of insurgency and sectarian violence since the U.S.-led invasion in 2003.

Source: Xinhua