Iraqi soldiers backed by US troops battled gunmen in central Baghdad early Tuesday, and explosions were heard in the area, police and witnesses said. Police said the clashes erupted when gunmen attacked Iraqi army checkpoints in the Haifa Street area, and that Iraqi soldiers appealed to the US military for help. American forces sealed off roads and joined Iraqi troops in raiding houses in pursuit of the gunmen, police said. The US military said in an e-mail that its troops "continue to conduct clearing operations in Baghdad and throughout Iraq," and that it would release more information on the Haifa Street clashes later Tuesday. The area is a Sunni insurgent stronghold in the center of the Iraqi capital, just to the north of the heavily fortified Green Zone, which houses the US and British Embassies, as well as many Iraqi government offices. Fighting broke out there late Saturday, and the Iraqi army reported killing 30 militants that night _ hours after Prime Minister Nouri al-Maliki announced a new open-ended security plan to oust sectarian killers from Baghdad. Iraqi state television said eight militants, including five Sudanese fighters, were captured Saturday near Haifa Street. Police reported finding the bodies of 27 torture victims dumped there earlier in the day. In other violence Tuesday, a policeman was wounded when a roadside bomb hit his patrol car in downtown Baghdad, police said. Another roadside bomb missed an Iraqi army patrol in Mosul but wounded an eight-year-old girl nearby, Iraqi Col. Eidan al-Jubouri said. Mosul is 360 kilometers (225 miles) northwest of Baghdad.