* Spc. Jeremy Morlock faces a maximum sentence of life in prison
* He is part of a larger case involving several soldiers
* They are accused of a conspiracy to kill and cover up, prosecutors say
* Photos were published of what appears to be Morlock posing over dead Afghan civilians

The trial of a soldier accused of killing Afghan citizens for sport is scheduled to begin Wednesday at Joint Base Lewis-McChord in Washington.

Spc. Jeremy Morlock is charged with three counts of murder. He is accused of killing one Afghan civilian in January 2010 with a grenade and rifle; killing another in May 2010 in a similar manner; and shooting a third to death in February 2010.

Morlock is one of two U.S. soldiers who are scheduled to be tried at Joint Base Lewis-McChord.

Pfc. Andrew Holmes is also facing charges in the case but a start date for his court martial has not been publicly announced.

Both are part of a larger case that involves several other soldiers, all accused of similar killings.

In all, officials charged 12 U.S. soldiers in what they called a conspiracy to kill Afghan civilians and cover it up, along with charges they mutilated corpses and kept grisly souvenirs.

Five of the soldiers face murder charges, while seven others are charged with participating in a cover-up.

Morlock was the first of the five to face an Article 32 hearing, the military equivalent of a grand jury hearing, at Joint Base Lewis-McChord.

If convicted, Morlock faces a maximum punishment of imprisonment for life without the possibility of parole, the military said.

Holmes is charged with the premeditated deaths of three civilians, possessing a dismembered human finger, wrongfully possessing photographs of human casualties and smoking hashish.

He is also accused of conspiring with Morlock to shoot at a civilian and then toss a grenade so it would look like the soldiers were under attack.

All of the accused men were members of a 2nd Infantry Division brigade operating near Kandahar in southern Afghanistan in 2009 and 2010.

The three others facing murder charges are Staff Sgt. Calvin Gibbs, of Billings, Montana; Adam Winfield, of Cape Coral, Florida; and Spc. Michael Wagnon, of Las Vegas, Nevada.

Authorities allege Gibbs kept finger bones, leg bones and a tooth from Afghan corpses. Wagnon allegedly kept a skull from a corpse, according to charging documents.

Several soldiers are charged with taking pictures of the corpses, and one soldier is charged with stabbing a corpse.

This week, German news outlet Der Spiegel published photographs of what they identified as Morlock and Holmes posing over the bodies of dead Afghan.

Two images show the soldiers kneeling by a bloody body sprawled over a patch of sand and grass. A third shows what appears to be two bodies propped up, back to back, against a post in front of a military vehicle.

The U.S. Army released a statement Monday calling the photographs "repugnant to us as human beings and contrary to the standards and values of the United States Army."

"We apologize for the distress these photos cause," the statement said.

Army officials asserted in the statement that ongoing court-martial proceedings related to the alleged atrocities "speak for themselves.

"The photos appear in stark contrast to the discipline, professionalism and respect that have characterized our soldiers' performance during nearly 10 years of sustained operations."