LOS ANGELES COUNTY, Calif. — A 33-year-old man is reportedly in custody after he shot his father on New Year’s Eve, and the father had allegedly killed his son’s girlfriend, friend and bedridden mother in a residence in Rowland Heights.

KTLA in Los Angeles reports deputies responded to calls about a gunshot victim just before 9 p.m. local time Thursday. At the residence, authorities found four people dead: two men ages 54 and 27, and two women ages 48 and 54. All had suffered gunshot wounds.

KTLA, citing the L.A. Times, reports the 54-year-old man had allegedly shot and killed his son’s bedridden mother, his girlfriend and a friend, and that the motive behind the shootings was still being investigated.

The son, identified as 33-year-old Christopher Morey, then reportedly wrestled his father to the ground, took the gun and fired once–fatally striking the man. The son then called police and was arrested.

“We’ll see what the D.A. wants to do,” Lt. John Corina told the Los Angeles Times. “We’re going to book him for what he did — he killed another human being. The district attorney will decide if it was justified.”

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