The Marine accused of killing unarmed civilians in Iraq pleaded guilty to dereliction of duty on Monday, according to the Associated Press.

Defense attorneys for Staff Sgt. Frank Wuterich reached a deal with prosecutors that that would mean a maximum of three months confinement for the Marine, said the AP.

The BBC reported that Wuterich was one of eight Marines who were originally charged in connection with the 2005 incident, but charges against six of them were dropped and one was acquitted.

On Nov. 19, 2005, Wutrich's squad entered an Iraqi house on a quest to find gunmen who were firing on them following the explosion of a roadside bomb, reported The Los Angeles Times. The exact events of the incident remain unclear, but 24 unarmed civilians, including women and children, were killed by the end, and Wutrich was later accused of manslaughter, assault and dereliction of duty.

The central issue of the case was whether "Wuterich reacted appropriately as a Marine squad leader in protecting his troops in the midst of a chaotic war or disregarded combat rules and ordered his men to shoot and blast indiscriminately at Iraqi civilians," according to the AP.

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The prosecution has been hampered by poor forensics and inconsistent testimony, according to the LA Times, although in an unsworn statement at his preliminary hearing Wutrich admitted that he ordered his Marines to "shoot first, ask questions later."

In 2006, Rep. John Murtha (D-Pa.), a vocal opponent of the Iraq war, said, "Our troops overreacted because of the pressure on them, and they killed innocent civilians in cold blood."

According to an NBC article from May 2006, "photos taken immediately after the incident show many of the victims were shot at close range, in the head and chest, execution-style."

The AP reported that Wuterich "regretted the loss of civilian lives but believed he was operating within military combat rules."

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