In charging documents, prosecutors said that an autopsy determined that Spc. Tevin Geike, 20, suffered a deep stab wound to his chest that cut through a rib and plunged through his heart.
Prosecutors charged Jeremiah Hill, 23, with first-degree murder, saying he approached Geike from behind and attacked him just as a verbal confrontation between two groups was calming down. Authorities also charged Cedarium Johnson, 21, and Ajoni Runnion-Bareford, 21, with rendering criminal assistance, saying they aided in disposing of the murder weapon.
The suspects and victim in the case were all soldiers at Joint Base Lewis-McChord. The soldiers charged in the case are scheduled to make their first court appearance Tuesday in Pierce County Superior Court.
Geike, of Summerville, S.C., was walking with two other soldiers early Saturday when words were exchanged with someone in a car. The vehicle, containing five people, stopped and four of the occupants got out to confront the three, prosecutors said.
Prosecutors said the groups were separating after realizing they were all active duty soldiers when Geike was fatally stabbed.
Two of the five suspects are cooperating with law enforcement and were not being held in custody, authorities said.
Prosecutors said the suspects eventually discarded the knife that was used in the attack into brush. Investigators believe they have found the weapon.
Baker reported from Seattle.