(CNN) -- Two mortar rounds on Monday night landed inside Baghdad's heavily fortified Green Zone, which houses Iraqi government offices and U.S. and British embassies, Iraqi and U.S. security officials told CNN. There was no immediate confirmation of casualties.
Similar incidents have occurred in recent weeks inside the protected area, formerly known as the International Zone. Three mortar rounds struck harmlessly inside the zone last month during a July 4 visit by U.S. Vice President Joe Biden. A day later, an Iraqi interior ministry officials told CNN that two mortar rounds hit the Green Zone.
And on July 27, two mortar rounds landed inside the area, according to ministry officials.
The district was a frequent target of rocket and mortar attacks during the worst of the war that followed the U.S. invasion in 2003. A similar attack struck during a Biden visit in September 2009.