Police say that James Little, an off-duty Pagedale reserve officer, shot and killed the fiancé of his ex-girlfriend over the weekend -- in the presence of Little's two young children and their mother.
William Dupree, 32, suffered multiple gunshot wounds to the head and was pronounced dead in front of his home on Sunday night. The fight broke out just after Little dropped off his two children, ages nine and twelve, at their mother's home, according to a probable cause statement on view below.
As the fight intensified, Little, 34, allegedly told his ex-girlfriend that he was going to kill her fiancé -- and then pulled out his gun.
The incident happened on the 2100 block of Farrar Street in north St. Louis by Hyde Park at around 6:30 p.m. on Sunday, police say.
Little and his ex-girlfriend had a "disagreement regarding the care of the children" when he arrived, the police report says.

When Little became "verbally abusive" toward the mother, Dupree allegedly began to defend her.
At this point, police say, Little asked Dupree to go back inside the house -- but he refused and stood between the man and his fiancé. This allegedly prompted Little to pull out his gun and fire multiple shots straight into Dupree's head.
Little's twelve-year-old stood in a nearby yard and his nine-year-old stood on the porch behind the murder victim, the report says.
The man is now facing charges of first-degree murder, armed criminal action and endangering the welfare of a child.
Dupree is the 36th homicide victim in the city of St. Louis in 2013.
Here's KSDK (Channel 5)'s segment on the shooting followed by the full SLMPD incident report and probable cause statement.
Incident: Homicide
Location: 2100 block of Farrar
Date/Time: 05/26/13 @ 18:25
Victim: William Dupree, 32-year old black male of the 2100 block of Farrar
Suspect: 35-year old black male (off-duty Pagedale Reserve Officer)
Officers responded to the above address and located the victim lying on his back in the front yard of his residence. The victim sustained multiple gunshot wounds to the head and was pronounced deceased at the scene. Investigation revealed that the suspect and the victim became involved in a verbal altercation when the suspect came to the residence to drop off a child he has in common with the victim's fiancé. The altercation turned physical at which time the suspect discharged his weapon. As a result of the investigation, the suspect was taken into custody. The investigation is ongoing.
Probable cause statement from the circuit attorney's office:
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