Rockets have smashed into Baghdad's heavily-fortified Green Zone, a day after radical Shi'ite cleric Moqtada al-Sadr called a ceasefire with Iraqi and coalition troops.
There have been no reports of fatalities from Monday's attack, which hit the compound housing the Iraqi government and the U.S. Embassy.
Despite the violence, a citywide curfew was lifted Monday. Businesses opened for the first time since al-Sadr's militants began fighting Iraqi and coalition forces nearly a week ago.
A vehicle ban remains in place in three Baghdad neighborhoods where al-Sadr's Mahdi Army has a strong presence.
Iraqi lawmakers say Iranian officials helped broker the truce with Al-Sadr's group Sunday.
They say Iraqi politicians close to Prime Minister Nouri al-Maliki traveled to Iran to ask authorities to pressure al-Sadr to stop the violence.
Iran has not confirmed the reports.
Witnesses say al-Sadr's fighters have also withdrawn from the streets of Basra Monday, prompting the government to ease its curfew there. The fighting in Baghdad and Basra killed more than 300 people since March 25.
Mr. Al-Maliki welcomed the ceasefire, calling it a step in the right direction.
Separately Monday, the U.S. military said coalition soldiers killed 25 criminals following an attack on coalition troops in eastern Baghdad Sunday.
It also said suspected terrorists killed six Iraqi policemen in a separate incident northeast of the town of Balad.
Some information for this report was provided by AFP, AP and Reuters.