Updated

Kaylin Gillis, the New York woman who authorities say died in a shooting after the car she was riding in turned up the wrong rural driveway, was in her boyfriend's car when a group of young people got lost on their way to a Saturday night party. 

Kevin Monahan, a 65-year-old reputed grouch who neighbors say hated trespassers and had a "short fuse," is sitting in jail in neighboring Warren County because Gillis' dad works in the one in their home of Washington County, according to local reports.

Gillis and a group of pals were looking for another friend's house in the area but had to deal with low cell reception, a lack of internet and dark, dirt roads, according to Washington County Sheriff Jeffrey J. Murphy.

They took a wrong turn up Monahan's driveway.

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Kaylin Gillis portait, left, in high school cheerleader uniform, right

Kaylin Gillis was in a car that turned down the wrong driveway in upstate New York Saturday night when the homeowner allegedly opened fire. The former high school cheerleader from nearby Schuylerville died of a gunshot wound. (Kaylin Gillis, Schuylerville Varsity Cheerleading/Facebook)

"We thought we were at the right address," Gillis' boyfriend, 19-year-old Blake Walsh, told NBC News Wednesday. "We didn’t have any cell service to figure it out."

When they made the realization, they tried turning around, he told the outlet.

"My friend said, ‘They’re shooting — go!’" Walsh said. "I tried to step on the gas as fast as I could, and that’s when the fatal shot came through."

But you can't outrun bullets.

And one struck Gillis, according to the sheriff.

Kevin D. Monahan

Kevin D. Monahan in a booking photo taken over the weekend. The 65-year-old man from rural New York is accused of fatally shooting a 20-year-old woman who was in a car that made a wrong turn up his private driveway. (Washington County Sheriff's Office)

NEW YORK WOMAN SHOT, KILLED BY HOMEOWNER AFTER CAR SHE WAS IN PULLED INTO WRONG DRIVEWAY

Neighbors heard the noise and grabbed their phones. At the same time, Walsh and another friend, driving a separate vehicle, raced up the rural road in search of cell service.

I can’t even fathom what would make a person shoot at a car that was in their driveway if they didn’t even know the people in the car.

— Hebron Town Supervisor Brian R. Campbell

At 9:53 p.m. Saturday, authorities received the first 911 call, reporting a shooting victim, Sheriff Murphy said. First responders raced to Cemetery Road in Hebron and attempted to treat Gillis, but she succumbed to her wounds.

Gillis petting a goat

Kaylin Gillis loved dolphins and goats and wanted to be a veterinarian or marine biologist, according to an online obituary. (Kaylin Gillis/Facebook)

A separate call reported gunfire 5 miles away, on Patterson Hill Road, where Monahan lives, according to the sheriff. Deputies went there, but the sheriff said he was "not cooperative" and refused to come outside and speak with responding deputies. After a standoff of several hours and with the assistance of a state police special operations team, he was arrested.

Hebron Town Supervisor Brian Campbell called it the "saddest and most inexcusable event" in the town's history.

"I can’t even fathom what would make a person shoot at a car that was in their driveway if they didn’t even know the people in the car," he said in a statement posted to the town's website. "I can’t tell you the number of times I’ve been awakened in the early hours of the morning...I always hurried down the stairs to try to get there as quickly as I could to help whoever must be in need. Never once, did I consider my own safety, or think that I needed to find a gun. I figured if someone was at my door they may need help."

NEW YORK WOMAN SHOT, KILLED AFTER BEING DRIVEN TO WRONG ADDRESS

Washington County Sheriff Jeffrey Murphy delivers an update

Washington County Sheriff Jeffrey Murphy delivers an update on the shooting death of Kaylin Gillis. Speaking to reporters earlier this week, he said the car she was traveling in had been driven up the wrong driveway. Homeowner Kevin Monahan allegedly opened fire before her friends could turn around and leave. (Washington County Sheriff's Office)

Gillis and her friends had gone to Monahan's driveway in error, in an area with dirt roads, low cell service and no internet connectivity, Murphy said Monday.

"They were basically looking for their friend's house, got mistaken and drove up his driveway," Murphy said.

A friend named Dallas Salls told the New York Times that a group of fellow graduates from Gillis' hometown of Schuylerville was having a party. Gillis and her friends were on their way there, and apparently had trouble finding it.

"It’s shocking, but I’m not surprised," Monahan’s next-door neighbor, Adam Matthews, told the New York Post. "He had a short fuse. There was never any doubt he had a short fuse."

Matthews called his neighbor a "narcissist" and said he often fumed over trespassers on his rural driveway.

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"It was always, ‘People just drive up my driveway, and they think it’s a road,’" he told the paper. "He was very adamant people didn’t come up, and for a long time he kept the bottom of his driveway gated because so many people did mistake it for a roadway because it’s so wide at the bottom."

It’s shocking, but I’m not surprised.

— Adam Matthews, Monahan’s next-door neighbor

Monahan is due back in court on April 25 on a second-degree murder charge.

His lawyer, Kurt Mausert, told the New York Times that his "elderly" client could reasonably be afraid of multiple vehicles speeding up his driveway at night.

"Is that a fear-inducing scenario? Well maybe it is," he told the paper. "It is not the simple scenario of these people took a wrong turn and within 20 seconds of them taking the wrong turn, this guy’s on his deck blasting away."

A woman who answered the phone at Mausert's office Wednesday morning said he was not immediately available for comment. 

Speaking separately with CBS News, he denied there was a standoff with police and said he was on the phone with Monahan while officers were outside without a warrant. He said he urged his client to surrender peacefully after he learned of Gillis' death.

Monahan's wife, believed to be home at the time of the shooting, did not immediately respond to messages seeking comment.

Kaylin Gillis wanted to be a vet and never missed 'Sunday dinner at Mi Mi's,' until this week

Gillis turned 20 on Feb. 23. She wanted to be a veterinarian or marine biologist, according to an online obituary.

Kaylin Gillis

Kaylin Gillis in an undated photo. She turned 20 in late February and died Saturday of a gunshot wound after she and a group of friends drove down the wrong driveway in rural upstate New York, according to authorities. (GoFundMe)

She loved animals, and photos on her Facebook and that of Walsh show her feeding packs of them at the zoo, at the beach and elsewhere.

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She was a varsity cheerleader and an artist who loved Disney movies, dolphins, tacos and ice cream.

She will be laid to rest Friday.

In lieu of flowers, her family is asking for donations to your local branch of the American Society for the Prevention of Cruelty to Animals – or to a GoFundMe campaign set up to create a scholarship in her name.