Authorities say the young Florida woman who was allegedly obsessed with the Columbine shooting is dead.

Jefferson County Sheriff Jeff Shrader told reporters Wednesday that the FBI found 18-year-old Sol Pais dead from an apparent self-inflicted gunshot wound.

The FBI had said that Sol Pais, flew to Colorado on Monday night and bought a pump-action shotgun and ammunition.

Authorities initially said she "made threats to commit an act of violence in the Denver metropolitan area."

The alleged threats led to the closure of school for more than half a million students on Colorado's Front Range Wednesday.  

The threats came days before the 20th anniversary of the deadly shooting at Columbine High School.

The Jefferson County Sheriff's Office and the FBI say Pais traveled to Colorado from Miami on Monday night and bought a pump-action shotgun and ammunition.

On Tuesday, some schools released their students after additional security was called in and canceled evening activities or moved them inside.

"We always have heightened awareness close to high-profile anniversaries like this," Billinger said.

The FBI's Rocky Mountain Safe Streets Task Force issued a notice Tuesday describing Pais as "infatuated with (the) Columbine school shooting."

Sheriff's spokesman Mike Taplin said the threats she made were general and not specific to any school.

The Denver Post reported that a call to a phone number listed for Pais' parents in Surfside, Florida, was interrupted by a man who identified himself as an FBI agent and said he was interviewing them.

Surfside Police Sgt. Marian Cruz confirmed that her parents last saw her on Sunday and reported her missing on Monday. The Miami Herald and WTVJ are reporting that neighbors say the teen is a senior at Miami Beach High School.

Two teenage gunmen attacked Columbine on April 20, 1999, killing 12 classmates and a teacher.

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