Florida teenager Sol Pais likely killed herself Monday evening on Mount Evans, never knowing that she was the target of a police dragnet more than 50 miles away or that her actions had incited panic as the 20th anniversary of Columbine approached, said the Clear Creek County undersheriff who led the search for the young woman on the mountain.

Pais, who was from Miami, would have been on a remote mountainside without cellphone service, no car and lacking the gear to survive the brutal weather conditions. There were no credit card purchases or cellphone pings that would have indicated she left Mount Evans once a rideshare driver dropped her off late Monday afternoon.

“She had no idea what occurred from late Monday afternoon to Tuesday when a search for her began and to Wednesday when her body was found,” Clear Creek County Undersheriff Bruce Snelling told The Denver Post. “The logical likelihood was she was here to end her journey.”

Snelling was part of a sheriff’s tactical team searching the mountain for Pais. They followed footprints in deep snow, interviewed the rideshare driver who took her to the area and talked to experts to try to understand her mindset. Eventually, they found her body, which appeared to have been dead for more than 24 hours, about three-quarters of a mile from Echo Lake Lodge.

Even if Pais waited until Tuesday or even early Wednesday morning to die, her cellphone would not have had a signal at 11,000 to 12,000 feet of elevation on the western slope of Mount Evans, Snelling said.

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“There was no way to find out what was going on based on where she was at,” Snelling said.

Pais, a high school senior, purchased three one-way airplane tickets to Denver for consecutive days and left her Miami home Monday. Authorities have said she arrived in Denver late Monday morning and then went to a gun shop near Littleton, where she purchased a pump-action shotgun and two boxes of ammunition. She then headed to the mountain.

The teenager’s parents on Monday reported her missing to local police, who called the Miami FBI office Tuesday. Miami agents informed their Denver counterparts that same day.

Investigators had discovered Pais was infatuated with the Columbine shooting. An online journal she kept included sketches of one of the killers and of guns. Social media posts along with comments she made to others led the FBI to see her as a credible threat, Dean Phillips, special agent in charge of the Denver office, said Wednesday during a news conference. However, she never made a specific threat to a specific school, he said.

As the FBI began tracking Pais’ whereabouts, agents also began informing local law enforcement that Pais was in the area and that she was armed. Hundreds of schools along the Front Range canceled classes Wednesday as the manhunt intensified.

By the time a massive media campaign was unfolding, Snelling said, authorities had evidence that she was at Mount Evans with no means to come back to the city.

The FBI provided the Clear Creek Sheriff’s Office with information that showed Pais was dropped off 56 miles west of Columbine High School at a pullout on Highway 103 at the base of Mount Evans in Clear Creek County.

From that moment, the 18-year-old dressed in a black T-shirt and camouflaged pants was on foot, Snelling said. She had no tent, no sleeping bag and no coat.

The Clear Creek Sheriff’s Office never received any evidence that Pais planned to use the shotgun to shoot others, Snelling said.

“I had no direct information from the FBI that any of her writings indicated she would do a school shooting,” Snelling said. “She didn’t have a master plan.”

But Jefferson County Sheriff Jeff Shrader, whose jurisdiction includes Columbine High School, said there was strong, generalized evidence that an attack was imminent.

Because Pais bought a one-way ticket, purchased a gun and ammo, and expressed a fascination with Columbine, authorities had reason to be concerned, Shrader said.

“A lot of that added up to give me quite a bit of concern,” he said. “Knowing what we knew — until her body was found — there was a belief of a general threat.”

Even as schools began increasing security Tuesday afternoon, searches had begun in and around Mount Evans.

Shrader sent the Jefferson County mountain team. The FBI sent a team, Snelling said. And Clear Creek deputies began searching at the top of Colorado 103 near the Echo Lake Lodge.

Snelling interviewed the rideshare driver, who told him that he had dropped her off at a pull-out on Colorado 103 about 7 miles from Idaho Springs. Pais had told the driver she wanted to see snow, and the driver did not think that she appeared to be distraught or on edge. She got out of the car carrying a duffel bag and a gun case, Snelling said.

Snelling said he consulted with an FBI agent who specializes in cold cases as well as a nationally recognized police psychologist to understand her possible mind-set. After those conversations, Snelling said he developed three theories about what Pais was doing:

Pais could have traveled to Echo Lake Lodge to hide out or practice shooting but didn’t realize it was closed. Her cellphone didn’t work, so she was stuck in the wild.

After visiting Echo Lake, Pais could have hitchhiked to Idaho Springs and then called for another rideshare to get back to the metro area and carry out a shooting.

Or, Pais’ sole reason for flying to Colorado on a one-way ticket and heading to a mountain was because she intended to commit suicide.

“She went dark,” Snelling said. “There was no digital footprint anywhere. No phone. No credit card use. To me, that pointed to a near impossibility that this ill-equipped, 18-year-old teenage woman would fly from sea level in Florida to Colorado and then go up into the mountains with plans to go on a killing spree. I believed the third scenario was the most likely one.”

Searching on the mountain ended at dark Tuesday.

Snelling’s team resumed its work Wednesday morning. He pulled a class of SWAT trainees to accompany the sheriff’s alpine rescue volunteers as they fanned out from Echo Lake Lodge.

Almost two hours after their search began, deputies saw footprints veering off Resthouse Trail.

“There was a little flat spot in the woods, and that’s where we found Ms. Pais,” Snelling said. “It was isolated and off the beaten path. It was peaceful. She was by a tree stump. Everything she had brought with her was in arm’s length of her.”

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Pais’ body was still clothed in the same camouflage pants and black T-shirt, and she had a small duffel bag that contained two boxes of shotgun shells, he said.

It snowed later Wednesday, and Snelling said he was thankful that deputies’ work had led to the discovery. Otherwise, Pais’ tracks could have been buried and could have prevented anyone from finding her body until summer.

At the time of the discovery of Pais’ body, law enforcement and school officials were discussing shutting schools for another day.

“What would today be like if we hadn’t found Ms. Pais?” Snelling said Thursday morning. “We would be operating under the umbrella of fear with the Columbine anniversary approaching.”

When Pais’ body was found, there was a simultaneous sense of relief and sadness, Shrader said.

Snelling described the same feelings. He was proud that his team had found Pais and ended the panic and chaos along the Front Range.

“In the waning hours, I was struck by how sad it was,” Snelling said. “This poor, mentally ill girl needed help and probably never got it.”