ORANGE, Calif. (AP) — Police say a shooting at a Southern California office building that killed 4 people wasn't a random act of violence.

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Police Lt. Jennifer Amat says the gunman who opened fire Wednesday at an office building in Orange knew all the victims, either personally or through business.

However, a specific motive for the attack is unclear.

The dead include a 9-year-old boy.

Authorities say the attacker had a semiautomatic handgun, pepper spray, ammunition and handcuffs.

His target was a mobile home real estate business.

Police say he was wounded either by police or self-inflicted gunfire and is in critical but stable condition.

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