(Adds second incident) BAGHDAD, April 16 (Reuters) - U.S. forces killed three Iraqi policemen in a case of friendly fire during a raid against suspected al Qaeda militants in the insurgent stronghold of Ramadi on Monday, the U.S. military said. The military said in a statement that U.S. troops had come under small arms fire during a raid in Ramadi, west of Baghdad, and returned fire. Three men killed in the confrontation were later identified as Iraqi police. The military said its troops had "coordinated their operation and no Iraqi police were known to be in the area". The incident is under investigation. Seven suspected insurgents were also arrested in the raid. In a second possible case of accidental shooting on Monday, a man who claimed to be an airport highway security guard was shot dead during a raid in Baghdad, the U.S. military said. The U.S. military said in a statement that soldiers who had just secured a building encountered four armed men emerging from a palm grove. The raid was conducted in search of militants suspected of having ties to al Qaeda. The statement said coalition forces were trying to verify claims by local Iraqis at the scene that the man who was killed was a security worker and whether he had ties with other suspects.
