Unknown to the truck drivers, elements of the 1st Cavalry Division had pushed militants into the suburbs of Abu Graib, through which the convoy had to travel.

[2] That morning, five vehicles of the 724th armed with crew-served weapons escorted a convoy of 17 fuel trucks and two bobtail tractors operated by U.S. defense contractor KBR.

Enroute, the convoy ran through a well planned, large-scale ambush that included improvised explosive devices, rocket-propelled grenades and small arms, believed to be from one or more of al-Qaeda in Iraq, the Badr Organization, and the Mahdi Army.

The attack damaged or destroyed numerous convoy vehicles and those that made the turn on the overpass drove through the mob of insurgents that had been driven into the neighborhood the day before.

Three civilian contractors, Thomas Hamill, Timothy Bell and William Bradley, and U.S. Army soldiers Sergeant Elmer Krause and Private First Class Keith Matthew Maupin, disappeared.

As vehicle armor improved along with convoy tactics, the insurgents suffered heavy casualties during the Palm Sunday Ambush on March 20, 2005, which inspired them to resort more to improvised explosive devices as weapon of choice.

[6] Private First Class Jeremy Church was the first truck driver and Army Reserve soldier to receive the Silver Star Medal since the Vietnam War.

[8] Family members of two of the wounded and one of the killed civilians later sued KBR, charging that the company had knowingly placed its employees in a battle zone in spite of promises not to do so.

[10] In early 2010, KBR notified the U.S. Army that it would bill the U.S. government for any damages awards or legal expenses it incurred in relation to contract work it did in Iraq.

After his death was confirmed in 2008, Interstate 275 in his native Clermont County, Ohio was officially renamed Staff Sergeant Matt Maupin Memorial Freeway.