At least seven people were killed and more than a dozen others were injured, Monday, when a suicide car bomber attacked a security checkpoint in central Baghdad. The attack occurred on the one-year anniversary of the capture of former Iraqi leader Saddam Hussein.

The powerful blast was heard throughout much of Baghdad. It occurred about nine o'clock in the morning, outside of the so-called Green Zone. The area, which houses the interim government in Iraq along with several foreign embassies, is the most heavily protected section in the capital.

Authorities say a suicide car bomber, waiting in line to enter a checkpoint at the Green Zone, blew himself up. Numerous other vehicles were also destroyed. The blast occurred as many Iraqis were arriving to show up for work inside the Green Zone.

Checkpoints around the Green Zone have become one of several favorite targets of insurgents in the country, as they attempt to disrupt elections scheduled for next month. However, a senior interim government official says the attack on Monday could have been associated with the one year anniversary of the capture of Saddam Hussein, which occurred on December 13, 2003.

The same official says the insurgency, one year later, as he puts it, is "much stronger" than anyone had anticipated. However, he insists the insurgency would be brought under control and says elections will be held next month, as scheduled.

Sunday, eight American Marines were killed in the Anbar Province, which includes the cities Fallujah and Ramadi, west of Baghdad.

The military says the Marines were killed in two separate security and stabilization operations. However, military officials refused to release the exact nature of their deaths, citing security concerns for other Marine units operating in the area.

The deaths Sunday equaled the highest number of Marines killed in a single day, since a car bomb exploded outside of Falljuah, October 30.

Falljuah was the scene last month of a U.S.-led offensive to root out insurgent strongholds in the city.

The deaths Sunday occurred one day after American warplanes attacked Fallujah with missiles, as insurgents battled with coalition forces in the city.