DENVER -- The FBI's Denver office and local law enforcement are searching for a woman who allegedly made threats against schools in the Denver metro area Tuesday.
According to the FBI, Sol Pais is infatuated with the Columbine massacre and purchased a gun in the Denver area.
At a news conference Tuesday night, authorities revealed new details about the search.
According to Dean Phillips, the special agent in charge of the FBI in Denver, the Miami FBI office alerted the Denver office about the threat of Pais.
Phillips said Pais flew to Denver on Monday night. She then bought a pump-action shotgun and ammunition in the Denver area and went to the foothills of Jefferson County.
Those actions promoted the FBI to consider Pais a credible threat.
Phillips said the FBI is working with law enforcement throughout the metro area and it is tracking a significant number of leads.
"This has become a massive manhunt," Phillips said.
Pais is considered armed and extremely dangerous.
Voter records show Pais is from Surfside, Florida, in the Miami area.
Authorities described Pais as a white female who is 18 years old. She is about 5-foot-5. She was last seen wearing a black T-shirt, camouflage pants and black boots.
Anyone who sees Pais or knows where she might be is asked to contact the FBI tipline at 303-630-6227. Tips can also be sent by email.
Officials urged the public not to approach Pais.
About 2:45 p.m. Tuesday, the Colorado Department of Education recommended all Denver-area schools conduct a lockout and controlled release of students because of the threats.
As of 1:30 a.m. Wednesday, all major districts in the Denver area had canceled classes for Wednesday.