A mortar barrage struck the heavily fortified Green Zone in central Baghdad on Tuesday, while the Iraqi police said they collected 21 corpses in execution-style in the capital, an Interior Ministry source said.
"Several mortar rounds landed on the Green Zone, which houses the Iraqi government offices, U.S. and British embassies," the source told Xinhua on condition of anonymity.
It was not clear whether there is any casualty, he added.
The U.S. military has no immediate comment on the incident.
The zone is supposed to be the most secure area on the west bank of the Tigris River that bisects the Iraqi capital, but mortar and rocket attacks struck the area almost every day.
In addition, the source said that the police patrol found 21 unidentified bodies in Baghdad's neighborhoods during the past 24 hours.
Most of bodies were handcuffed, blindfolded, showing signs of torture with bullet holes in the chest and the head, he said.
Violence and the daily gruesome finding of unidentified corpses continued in the capital despite the U.S. and Iraqi security offensive, which has not achieved substantial progress in reducing violence in the war-torn country.