CONCORD (CBS SF) — A man who police say was attacking his elderly parents with a knife was fatally shot by Concord police officers in the parents’ home, authorities said Sunday.

The shooting occurred on the 900 block of Oasis Drive, located west of Oak Grove Road and north of David Avenue at around 11:45 a.m.

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An older couple, aged 85 and 90, called dispatchers and said their 60-year-old son was acting “erratically” and was possibly under the influence of drugs and alcohol, police spokesperson Cpl. David Petty said.

They told dispatchers their son was armed with a knife and a plastic gun.

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Neighbors had also called to report the man. As police arrived on the scene, they saw the man in the front yard with the plastic firearm. As officers approached him trying to de-escalate the situation, he retreated back into his parents’ home. Police then saw the father walk outside the house suffering from serious injuries.

Officers went inside the home and found the suspect “straddling” his mother while holding a knife; that is when the two officers fired their weapons at the 60-year-old son, police said. He was pronounced dead at the scene.

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Neighbor Steve Kramer said it was “sad” that the man’s father turned around when he heard the officers’ gunshots sound off from within the home.

“He kind of turned around, and that just broke my heart because it was like, knowing your son is probably…you know, whether he was acting like an idiot or not, it’s still your child,” Kramer said.

The two victims were transported to a local hospital Sunday evening and are being treated for serious injuries.

Concord police have had previous encounters with the 60-year-old man, Petty said. When asked about what kind of issues the man had, he said, “Psychological, drug and alcohol. We’ve been here a short time, but he’s been out in the yard and had some issues.”

Concord PD is working with investigators from the Contra Costa County District Attorney’s Office to find out more about the case.

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