Authorities say an Arizona state trooper shot and killed a Qatari man after he attacked the officer on routine patrol for drunk drivers on Friday. The US police officer spotted Mohamed Al Hashemi, 25, throw a street sign on to a road in suburban Phoenix late on Thursday and ordered him to pick it up, said Colonel Frank Milstead, director of the Department of Public Safety. Al Hashemi refused to replace the sign, then began walking in the middle of the road and would not obey commands to stop, Col Milstead said. Camera footage from the officer’s patrol vehicle shows the man appearing to comply with commands at first, then launching himself at the police officer. Trooper Hugh Grant used a stun gun but it did not subdue Al Hashemi. The video shows the men tussling, and at one point, Mr Al Hashemi throws the officer to the ground. The officer fired his weapon, killing Al Hashemi, the DPS chief said. “It was a vicious encounter,” Col Milstead said. “He was in a fight for his life.” Mr Grant was accompanied in his patrol on Friday by a woman from the group Mothers Against Drink Driving. “When he began to realise this was escalating, he was trying to keep her out of danger,” Col Milstead said. Authorities said they did not know if Al Hashemi was impaired. The trooper had injuries to his face and head and is resting at home. Authorities say Al Hashemi was arrested for trespassing at the Islamic Community Centre of Tempe on Wednesday. Police in the Phoenix suburb of Tempe responded to a disturbance at the mosque around 4.30am. At the centre's request, officers gave him a warning and told him not to return, police spokesman Greg Bacon said. Al Hashemi returned in the early afternoon and officers were called again. Mr Bacon said he was then arrested on a misdemeanour charge of trespassing and booked into jail. Al Hashemi was a former student at Arizona State University, which is based in Tempe, according to school officials. They did not provide other details.