The scene where a car bomb exploded near a market in eastern Baghdad, May 12, 2005

Insurgents in Iraq continued their campaign of violence Thursday, killing at least 15 people, including two officers from the defense and interior ministries. 

Insurgents killed two officers in Iraq's security forces in separate roadside ambushes in Baghdad Thursday.

Brigadier General Iyad Imad Mahdi was shot dead while driving to his office at the Ministry of Defense. Colonel Fadhil Mohammed Mubarak was on his way to the Ministry of Interior, where he headed the police control room, when he was caught in insurgent gunfire.

U.S. military officials say insurgents detonated four car bombs in Baghdad Thursday, including at least two suicide attacks.  Another two car bombs went off in the northern city of Kirkuk, 180 miles north of the capital.   A wave of attacks since the new Iraqi cabinet was announced two weeks ago has killed more than 300 people.

The attacks come despite a U.S. offensive in the desert of western Iraq, towards the Syrian border, aimed at stamping out followers of Abu Musab al-Zarqawi.  The Jordanian born Zarqawi is believed to be behind many of the insurgent attacks.

As Operation Matador continued into its fifth day, US troops in tanks and light armored vehicles rolled through desert outposts, while residents in the villages of Karabila and Saada reported heavy bombardments from U.S. artillery and aircraft.

Two Marines died and 14 were wounded when their armored transport ran into an explosive device on Wednesday.

At least five U.S. Marines and an estimated 100 insurgents have been killed in the US-led operation, one of the biggest in Iraq since the capture of Falluja six months ago.