An Iraqi police official said a sniper taking cover in a building in central Baghdad has opened fire on a checkpoint, according to AP. The official said one policeman has been killed and another wounded in the attack Thursday afternoon. Police have sealed off the area and are searching for the sniper, he added. The attack in the primarily commercial district Karradah neighborhood is the latest in a string of attacks against security forces in the area. Despite an overall decline in violence, insurgents have routinely targeted security forces in Baghdad.