HOUSTON, Texas (AA) – A father in Sacramento, California killed his three children Monday and then turned the gun on himself.

The murder-suicide happened at The Church shortly after 5 p.m. local time (0100GMT Tuesday).

Sgt. Rod Grassmann of the Sacramento County Sheriff’s Department said at a news conference that the father walked into the church and shot his three children, who were under the age of 15, as well as a fourth unidentified victim and then shot himself.

“Another senseless act of gun violence in America — this time in our backyard,” said California Gov. Gavin Newsom on Twitter.

“In a church with kids inside,” he continued. “Absolutely devastating.”

The sheriff’s department said it was a case of domestic violence.

Authorities are still investigating what led up to the tragic shooting.

“Our hearts go out to the victims, their families and their communities,” said Newsom.

“We are working closely with local law enforcement,” he added.