Fighting between Iraqi security forces and the Shiite militias continued for a second day Wednesday, leaving 8 people dead and 70 injured.

The clash started on the streets of Basra and Baghdad on Tuesday, with 40 people killed and 200 hundred wounded, as health officials reported to Reuters. The dead included Iraqi troops, police, militia members and civilians.

The supporters of Shiite cleric Muqtada al-Sadr began the fight as a protest movement following several arrests of its members.

The important cities and towns in southern Iraq were under night-time curfew, as Iraqi authorities tried to prevent violent outbreaks.

Iraq’s prime minister, Nuri al-Maliki, has requested that the Shiite militants surrender in 72 hours.

"Those who were deceived into carry weapons must deliver themselves and make a written pledge to promise they will not repeat such action within 72 hours," he said on Wednesday, according to Aljazeera.net.

"Otherwise, they will face the most severe penalties," he warned.

Police reported that early on Wednesday, a roadside bomb reportedly exploded near a vehicle in northern Basra, killing all the passengers. Also, the gun battles restarted in various districts of the city.

Basra residents told Reuters that there was heavy gunfire in the town, sounds of several explosions could be heard and gunmen could be seen planting roadside bombs. They said people are terrified and no one is going to work, as the streets are filled with gunmen.

The Mahdi militia, which is loyal to Sadr, was observing a cease-fire since summer. Since then the security increased throughout Iraq especially as more American troops were deployed, but their leader, Moktada al-Sadr, called for a civil disobedience campaign as retaliation for some unwarranted crackdowns on them. Al-Sadr's loyalists said they were very angry with the raids and detentions carried out against them by U.S. and Iraqi forces.

As Basra is Iraq’s biggest oil exporting center, there were worries that that oil exports could be affected, but Iraq’s Southern Oil Company assured the oil companies work as usually, given that the clashes are taking place far away, Reuters informed.