Luke Stein, 18, who was taken into custody in Colorado on Friday, Oct. 14, became a volunteer firefighter in Alpine and Demarest earlier this year, records show.
He was driving a Jeep Grand Cherokee with blue and white emergency lights on the dashboard when he pursued and then deliberately rear-ended the victims' Honda Pilot on Route 9W just after midnight on Monday, Oct. 10, a complaint on file in Superior Court in Hackensack alleges.
Stein lives in Cresskill with his mother, Wendy Stein, and stepfather Manuel "Manny" Alfonso, a career law enforcement officer with federal and state experience who ran for Bergen County sheriff six years ago.
According to the complaint filed by a Bergen County prosecutor's detective, Stein was upset after hearing that a friend had been assaulted at a party attended by the group.
"Accompanied by friends, Stein proceeded to that address," the complaint says.
The group had left, so Stein got into the Jeep with his friends and went looking for them, detectives charged.
Mikkel Leutgeb, who was driving the Honda, told investigators he and his friends left the party on Schaffer Road in Alpine "because a person had a gun," according to the detective's report.
The detective said Leutgeb was stopped at a red light when Stein caught up to them.
He "activated his emergency lights and the Honda began to pull over," the complaint filed by Bergen County Prosecutor's Detective Daniel Tanelli says. "At that point, Stein struck the rear of the Honda.
"After the impact, the Honda sped off with Stein accelerating behind it," it says. "Witnesses reported that the vehicles were traveling in excess of 100 MPH."
The Pilot rolled and crashed into the woods in front of the Montammy Golf Club in Alpine a short time later, authorities said.
Two Tenafly teens were critically injured and two others were severely injured. A fifth was seriously injured.
SEE: Teens Critically Injured In Road-Rage Rollover On Route 9W
According to the complaint, those in Stein's Jeep "did not see the Honda crash but turned into the Montammy Golf Club because they believed the Honda must have turned there. They proceeded into the club and began to search the property for the Honda, but were unable to locate it."
So they left, it says.
Stein was headed home when he received an emergency alert on his firefighter pager to respond to the golf club for a motor vehicle accident, according to the complaint.
"He responded to Alpine Fire/EMS headquarters and returned to the scene with emergency personnel," it says.
Authorities said they found Stein's Jeep Grand Cherokee in the driveway of his folks' East Madison Avenue home in Cresskill.
"A subsequent search of the vehicle, pursuant to a court order, revealed front end damage and an emergency light bar mounted on the dash," according to the complaint.
Detectives from Prosecutor Musella's Fatal Accident Investigations Unit charged Stein with aggravated assault -- for the high-speed pursuit with emergency lights flashing -- and impersonating a law enforcement officer.
He was taken into custody on their warrant on Friday by police at the University of Colorado in Boulder, where he goes to school.
Stein will remain held in the Boulder County Jail pending extradition proceedings to return him back to New Jersey to face the charges in Superior Court in Hackensack.
CLICK HERE FOR: BACKGROUND ON THE VICTIMS
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