LOS ANGELES » Police believe a man stabbed his three young sons to death in the back seat of their car outside a South Los Angeles elementary school before turning the knife on himself.

Los Angeles Police Chief Charlie Beck says the boys, ages 8 to 12, were found dead Wednesday morning in the back of an SUV. Their father was bleeding from stab wounds in the front seat and was taken to a hospital in critical condition.

Officer Matthew Ludwig later said detectives believe the father is the one who killed the boys, and there are no other suspects. The motive is being investigated.

Officer Liliana Preciado says the father’s stab wounds are believed to be self-inflicted.

Beck says the crime scene was horrific and that "it is a sad day in LA."