One-Way Airplane Tickets, Threats Alerted FBI To Sol Pais

DENVER, CO – The Florida woman who inspired a massive manhunt through the metro Denver area is thought to have taken her own life near Mt. Evans, the FBI said Wednesday. The woman's obsession with the Columbine shooting, as well as purchasing multiple one-way airline tickets from Florida to Denver, alerted law enforcement to the threat, the agency said.

Investigators along with members of the Clear Creek County Sheriff's Department started an early-morning expanded search in in the area where Sol Pais, 18, had been dropped off by a rideshare driver, FBI Director Dane Phillips said.

Related: Colorado's Quick Response to School Threat Was Well-Rehearsed

Her body was found around 10:40 a.m., and it appeared she had taken her life with a shotgun purchased in Colorado, Phillips said. Investigators are still waiting for autopsy results.

Phillips said irregular behavior by Pais and things she had said to others caught the attention of local police in her hometown of Surfside, Florida. On both social media and in person, Pais had talked about the Columbine School shooting, an interest which investigators described as an "infatuation." Unspecified people who knew Pais passed their concerns to local police, who in turn passed the threat on to the Miami FBI, Phillips said.

Pais had called several Denver-area gun stores from Florida before choosing Colorado Gun Broker in Littleton to purchase a pump-action shotgun and multiple boxes of ammunition. Josh Rayburn, owner of Colorado Gun Broker, told Denver7 that Pais had a clear background check and his sales team had no reason to believe she was a threat. The shotgun cost $300, he said. Pais reportedly told gun-shop employees she planned to "do some turkey hunting."

The FBI's Rocky Mountain Safe Streets Task Force and members of various Colorado law enforcement agencies showed up at the gun shop after Pais had already purchased the weapon, Phillips said.

Phillips said the investigation is ongoing and that law enforcement officials were tracking down more leads and wading through social media and online evidence, "to make sure there aren't any accomplices."

Denver-area schools canceled classes for Wednesday, April 17 due to the threat. The 20th anniversary of the Columbine school shooting is on Saturday.

Related: Denver-Area Parents Will Be Talking to Kids About School Violence

"We are relieved that the threat to our schools and community is no longer present," Jefferson County Schools Superintendent Jason Glass said. Glass said Jeffco schools plan on returning to normal operations on Thursday with heightened security. Other events planned for the weekend will continue, Glass said.

"As confirmed by the FBI, Sol Pais has been found deceased and the potential threat is over," Colorado Gov. Jared Polis said in a statement after the manhunt ended.

"It’s times like these that help us appreciate friendship, family, and community. Today, parents across Colorado - including me - are hugging their children a little tighter. Together we thank law enforcement for their swift and diligent actions over the past 24 hours to keep Coloradans safe, and we will continue to be vigilant against threats to our community."

In Surfside, Florida, a man who identified himself as Pais's father told ABC News that he last saw his daughter on Sunday. He told reporters the ordeal has "been a nightmare." Neighbors told ABC that Sol Pais was a student at Miami Beach High School.

It was still unclear what threats Pais had made, and how she came to the attention of the Miami FBI.

Pais was described as a white female, 18 years old, approximately 5'5" in height, with brown hair. She was last seen wearing a black t-shirt, camouflage pants, and black boots.

JeffCo Schools initiated a "lockout" Tuesday afternoon, but released students at their regular times. Extra school security and officers were on hand across the district to watch the student dismissal. A lock-out is a soft emergency response where no one is permitted to leave or enter the buildings.

Here is a list of districts that canceled class today:

• 27J Schools
• Adams 12 5Star
• Adams 14
• Aurora Public Schools
• Boulder Valley
• Cherry Creek Schools
• Clear Creek
• Denver Public Schools
• Douglas County School District
• Elizabeth Schools
• Englewood Schools
• Greeley/Evans Schools
• Jefferson County Schools
• Littleton Public Schools
• Mapleton Public Schools
• Poudre School District
• Sheridan Schools
• St. Vrain Valley School District
• Thompson School District
• Westminster Public Schools
• Weld County RE3J
• Weld County Re-4
• Weld County Re-8

See a complete list of school closures on the KMGH television station website.

The Colorado Board of Education and law enforcement made the decision to close schools based on consultation with the FBI and other law enforcement agencies at a 3 a.m conference call Wednesday morning.

On April 20, 1999, two teens went on a shooting spree at Columbine High School in Littleton, killing 13 people and wounding more than 20 others before they killed themselves.