The charge papers filed by prosecutors allege four enlisted Marines assigned to Kilo Company, 3rd Battalion, 1st Marine Regiment, used automatic weapons, a pistol and a grenade to kill 24 Iraqi civilians in the city, the San Diego Union Tribune reported Sunday.

The papers detail the specific allegations against Staff Sgt. Frank Wuterich, Sgt. Sanick Dela Cruz and Lance Cpls. Justin Sharratt and Stephen Tatum.

Wuterich, the highest-ranking service member allegedly present at the killings, faces the most severe charges: 13 counts of murder, two counts of prompting someone to commit an offense and one count of making a false official statement.

"While engaging in an act inherently dangerous to another and evincing a wanton disregard for human life, (Wuterich did) murder six persons inside a house identified as House 1 by: advising the Marines under his charge, prior to the Marines' entry into House 1, to 'shoot first and ask questions later' or words to that effect," the papers say.