UPDATE: (12:50 PM): California officials say a man under a restraining order and not supposed to have a gun fatally shot his three daughters, a chaperone and himself during a supervised visit with the girls.

Investigators are trying to piece together the father’s motive and how he got the weapon used in the shooting Monday at a Sacramento church.

Authorities say a man shot and killed his three children, one other person, along with himself at a church in Sacramento, California.

A sheriff's official said deputies who were responding to reports of gunfire at around 5 p.m. local time found five people dead, including the shooter, at the church in the city's Arden-Arcade neighborhood. He said the victims included three juveniles under 15 years of age. The identity of an additional victim wasn't immediately known.

Sgt. Rod Grassmann with the Sacramento County Sheriff’s Office said he didn't know if the family members belonged to the church, the Associated Press reported. Grassmann said officials are investigating the scene as a domestic violence incident.

Reports said that it wasn't immediately clear how many others were at the church at the time, or if there were any services or activities happening during the shooting.