LITTLETON, Colo. (AP) -- UPDATE 4/17/19 @ 1:50 p.m.
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 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."
UPDATE 4/17/19 @ 1:05 p.m.
FBI agents hunting a young Florida woman accused of threatening violence in the Denver area ahead of the 20th anniversary of Columbine said Wednesday she is "no longer a threat to the community." There was no immediate explanation from the FBI.
The announcement, made via Twitter, came after an all-out manhunt for 18-year-old Sol Pais, whose alleged threat led the closing of Denver-area public schools Wednesday as a precaution.
Agents had focused the search around the base of Mount Evans, a popular recreational area about 60 miles southwest of Denver.
During the manhunt, the FBI said Pais was "infatuated" with Columbine and threatened violence ahead of Saturday's anniversary of the attack that killed 13 people at Columbine High School in 1999. The FBI described her "extremely dangerous."
The Miami Beach high school student flew to Colorado on Monday night and bought a pump-action shotgun and ammunition, authorities said.
All classes and extracurricular activities for about a half-million students were canceled as a precaution, though sheriff's spokesman Mike Taplin said the young woman's threats were general and not specific to any school.
"This has become a massive manhunt ... and every law enforcement agency is participating and helping in this effort," said Dean Phillips, agent in charge of the FBI in Denver.
Authorities said Pais was last seen not far from Columbine - in the Jefferson County foothills outside Denver - in a black T-shirt, camouflage pants and black boots.
The alert also said police who come into contact with her should detain her and evaluate her mental health.
Colorado Gov. Jared Polis said federal, state and local law enforcement were "dedicating all of their resources to locate this dangerous individual."
"We know that there is a lot of anxiety right now in Colorado," Polis said in a statement.
Because of the threat, Columbine and more than 20 other schools outside Denver locked their doors for nearly three hours Tuesday afternoon, and some canceled evening activities or moved them inside.
Pais' parents last saw her on Sunday and reported her missing to Florida authorities on Monday night, police in Surfside, Florida, said.
Messages left by The Associated Press at two numbers listed for Pais' relatives in Florida were not immediately returned, while another number was disconnected.
Adam Charni, a Miami Beach High School senior, said Pais dressed in black and kept mostly to herself. He said he was "baffled" to learn she was the person authorities in Colorado were searching for.
Another classmate, 17-year-old junior Drew Burnstine, said Pais was a quiet, smart student who sat alone in class and "never caused problems or indicated that she wanted to harm anyone."
Two teenage gunmen attacked Columbine on April 20, 1999, killing 12 classmates and a teacher before taking their own lives.
State Rep. Patrick Neville, the Republican House minority leader, was a 15-year-old sophomore at Columbine High at the time of the shooting and now has three school-age daughters.
"It wasn't easy for me to explain to my kids what was going on last night," Neville said on the House floor Wednesday.
UPDATE 4/16/19 @ 5:32 p.m.
Students are leaving classes after tightened security at Columbine High School and over 20 other Denver-area high schools after a lockdown caused by a possible threat.
Students wearing backpacks came out the main door at Columbine on Tuesday afternoon, soon after school officials announced that students in all the schools put on lockdown were safe and would be dismissed at their normal times. The students walked to crosswalks and buses parked near the entrance.
Officials said after school activities will be held at all schools except Columbine, but didn't explain why.
A spokesman for the Jefferson County Sheriff's Office, Mike Taplin, said the lockdowns involved an FBI investigation but he couldn't provide any details. The sheriff's office previously said the lockdowns were prompted by an investigation into what appeared to be a credible threat possibly involving the schools
The lockdowns come just days before the 20th anniversary of a mass shooting at the school that killed 12 students and a teacher.
UPDATE 4/16/19 @ 4:35 p.m.
Authorities say tightened security at Columbine High School and about a dozen other Denver-area schools is related to an FBI investigation.
A spokesman for the Jefferson County Sheriff's Office, Mike Taplin, said Tuesday's school lockdowns involved an FBI investigation but he couldn't provide any details. The sheriff's office previously said the lockdowns were prompted by its investigation into what appears to be a credible threat possibly involving the schools
A message left for an FBI spokeswoman wasn't immediately returned.
School officials say the doors were locked but classes were continuing at Columbine and two other nearby schools and at other schools farther away in the same district.
The lockdowns come just days before the 20th anniversary of a mass shooting at the school that killed 12 students and a teacher. There was no immediate indication whether there was any connection to the anniversary.
ORIGINAL STORY 4/16/19
Columbine High School and about a dozen other schools are on lockdown as law enforcement says it is investigating what appears to be a credible threat possibly involving the schools.
School officials say the doors were locked but classes were continuing Tuesday at Columbine and two other nearby schools and at other schools farther away in the district.
The Jefferson County Sheriff's Office said deputies were posted at the schools involved.
The lockdown comes just days before the 20th anniversary of a mass shooting at the school that killed 12 students and a teacher. There was no immediate indication whether Tuesday's lockdown has any connection to the anniversary.