Luke G. Stein, 18, of Cresskill was booked into the Bergen County Jail on Monday, Oct. 17, after being brought from the Boulder County Jail in Colorado.
Authorities there seized Stein this past Friday on a warrant from the Bergen County Prosecutor's Office that charges him with five counts of aggravated assault, as well as impersonating a law enforcement officer.
Restraining orders were also being sought to prevent him from contacting the victims, Daily Voice has learned.
Stein, who attends the University of Colorado, became a volunteer firefighter in Alpine and Demarest earlier this year.
Authorities said 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 in Alpine just after midnight last Monday.
The group's SUV sped off and a short time later rolled and crashed into the woods in front of the Montammy Golf Club in Alpine.
Stein, meanwhile, went to the East Madison Avenue home in Cresskill of 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, authorities said.
He returned to the scene in a different vehicle as a responder a short time later, a complaint on file in Superior Court in Hackensack alleges.
Stein was upset after hearing that a friend had been assaulted earlier that night at a party attended by the group at a private residence in Alpine, according to the complaint.
"Accompanied by friends, Stein proceeded to that address," it says.
The group had left, so Stein got into the Jeep with his friends and went looking for them, a Bergen County prosecutor's detective charged in the complaint.
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 investigator's report.
Leutgeb was stopped at a red light when Stein caught up to them, it says.
He "activated his emergency lights and the Honda began to pull over," the complaint alleges. "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 crash occurred moments later.
Leutgeb suffered a fractured lumbar, a broken leg and facial damage, according to his family (GoFundMe: Mikkel Leutgeb Recovery).
Variously injured -- critically, severely and seriously -- were:
Ariana Grant, whose injuries include a severely lacerated scalp, broken ribs, pierced lungs, fractured vertebrae in her neck and spine and a broken arm and ankle, according to her aunt, Wende Grant Green (GoFundMe: Ariana Grant Recovery);
Jonathan Battaglia, who spent his 18th birthday recovering at Hackensack University Medical Center from punctured lungs, a broken leg, several fractures, a gash in his head and brain hemorrhaging, according to GoFundMe information approved by his family (GoFundMe: Jonathan Battaglia Recovery);
Lital Aburus, who "underwent a 7-hour surgery on her shattered arm, in which rods and pins are now permanently holding together her bones," the Tenafly High School Home School Association wrote. Lital "suffered numerous lacerations requiring countless stitches on her face and hands, broken bones in her back, bruised lungs, and broken jaw, eye socket, and teeth and palate." (GoFundMe: Lital Alburus Recovery);
Kevin Trejos, who suffered two compound lumbar fractures, a bruised lung, a respiratory infection and cuts on the hip, Deutsch wrote on a GoFundMe page he created for his friend (GoFundMe: Kevin Trejos Recovery).
SEE: Teens Critically Injured In Road-Rage Rollover On Route 9W
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," the complaint filed by Bergen County Prosecutor's Detective Daniel Tanelli says. "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 (story continues below).
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' home.
"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.
SEE: Driver Seized In Colorado In Route 9W Crash That Critically Injured Bergen County Teens
Click here to follow Daily Voice Saddle Brook-Elmwood Park and receive free news updates.