Family members fled as Christopher Koski, 24, fired a shotgun blast in the house and threw two rifles out the window, Detective Lt. Edward Kane said.
A member of the Bergen County Regional Crisis Negotiation Team eventually talked him out, but not before Koski “pointed a loaded handgun out a second-floor window” at the tactical unit, Kane said.
Authorities seized several firearms from the home, the lieutenant said.
The standoff began around 1 a.m., after Koski fired a shotgun, damaging the house and frightening family members, Kane said.
The recent Pace University graduate Koski apparently had a fight with his girlfriend at a party, then argued with family members before returning home and grabbing the shotgun, a law enforcement source said.
Officers from Upper Saddle River, Allendale, Saddle River, and Montvale responded before a Bergen County Regional S.W.A.T. Team was summoned.
After talking with negotiators by phone, Koski emerged just after 4:30 a.m., surrendering peacefully.
"The scary part is that this could have gone either way," one responder said. "You really didn't know for awhile there."
Koski was taken to New Bridge Medical Center in Paramus by the Upper Saddle River Volunteer Ambulance Corps pending transfer to the Bergen County Jail.
Police charged him with aggravated assault, possession of hollow-point bullets and weapons offenses.
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