QUETTA: Gunmen riding a motorcycle killed three policemen at a checkpoint in Quetta on Sunday before fleeing the scene, authorities said, in an attack later claimed by a local affiliate of the Islamic State group. The incident occurred on the main Saryab Road, senior police official Abdul Razzaq Cheema told AFP. Doctor Farid Sumalani, head of the Sandeman Provincial Hospital, confirmed the incident. Ali Bin Sufyan, a spokesman for the Al Alami branch of the Lashkar-e-Jhangvi (LeJ) militant group, sent AFP a text message taking credit for the shooting. IS has been making inroads in the country through alliances with local militant outfits such as LeJ and the Jamaat-ul-Ahrar faction of the Pakistani Taliban. LeJ has claimed joint responsibility along with IS for several major attacks in the region including one on lawyers in Quetta that killed more than 70 people. Earlier this week IS said it had killed two Chinese citizens who were kidnapped last month by armed gunmen in Quetta. The group made the claim in a brief Arabic message carried by its Amaq news agency on Thursday, though there was no immediate confirmation from Chinese or Pakistani officials. Separately, three security officials were injured after an improvised explosive device (IED) seemingly targeted their vehicle in the Johan area of Kalat on Sunday, security sources said.