US and Iraqi forces killed at least 13 gunmen in sporadic overnight clashes in the Baghdad Shiite neighborhood of Sadr City, the US military said on Saturday.

During the clashes US forces fired one Hellfire missile from a US drone aircraft and two 122 mm rounds from a M1A2 Abrams tank against the gunmen who fought the troops with their roadside bombs, rocket propelled grenades, machine guns and small arms fire, a military statement said.

On Friday, the US military announced in a statement that its air forces conducted air strikes in the neighborhood of Sadr City and in the southern city of Basra, 550 km south of Baghdad, killing at least 12 suspected insurgents.

Sadr City is the main stronghold of the Shiite Mahdi Army militia loyal to cleric Muqtada al-Sadr. Iraqi troops supported by the US military have been fighting on the streets in the sprawling heavy-populated district in eastern the capital.

Iraqi officials with the interior ministry claimed that at least 70 people have been killed and dozens wounded after the clashed erupted last Sunday.

Late on March, fierce clashes between Shiite Mahdi Army militia and US-backed Iraqi security forces raged the main cities in the Shiite south, as Iraqi security forces launched a massive offensive,dubbed "Operation Cavalry Assault" aimed at cracking down militias in Basra, some 550 km south of Baghdad.

Tensions run high between the Sadr followers and Prime Minister Nuri al-Maliki's government as Maliki warned that Sadr must disband the Mahdi Army militia or will be barred from the political process and the upcoming provincial elections.

On the other hand, Sadr politicians accused Maliki's government of imposing "political liquidation" and threatened to lift the ceasefire on the Mahdi Army militia first ordered by Sadr last August, if the security forces continues to attack Sadr followers.

(Xinhua News Agency April 12, 2008)