As many as 30 gunmen on Thursday attacked a number of police checkpoints in the Mohammed Al-Qassem Highway in central Baghdad. Eyewitnesses told KUNA the gunmen stepped out of their cars and opened fire at the police checkpoints. They said the clashes lasted for half an hour. No reports on casualties were available. Patrols of Iraqi army and US troops, who were rushed to the scene, cordoned off the whole area and kept civilians out of it.