The California man who shot his two adult daughters on Monday, leaving one dead and the other critically injured before committing suicide, was a Vietnam veteran who had received a Purple Heart.

Anthony Alvarez, 63, killed his daughters while his three young grandchildren were inside their Orosi, Calif. home. His eight-year-old granddaughter called to report the incident after she heard the gunshots that killed the trio, according to CBS 47.

Police found Alvarez dead from what appeared to be a self-inflicted gunshot wound, the Tulare County Sheriff's Department announced in a statement.

"It's a very cut-and-dried case," sheriff's spokeswoman sergeant Chris Douglass told the Associated Press.

Alvarez received his Purple Heart after military service in Vietnam as a Marine. While police are continuing investigations of the Memorial Day bloodbath, it remains unclear why the recipient of one of the highest merits in the Armed Forces committed the killings on the holiday.

Authorities have not released information on possible motives.

Alvarez left 37-year-old Jennifer Kimble, the mother of the eight-year-old who called the police, dead while leaving his 33-year-old daughter Valerie Alvarez, who was rushed to a hospital in Fresno, critically injured.

Kimble worked as a cafeteria worker at a nearby elementary school, according to the Associated Press. Kimble's two older daughters, ages 11 and 13, were also inside of the home during the time of the incident.

Authorities will conduct a full autopsy later this week while continuing to examine possible motives, police told the Associated Press.