(DENVER) -- Colorado authorities are searching for a woman they say is "infatuated" with the 1999 Columbine High School shooting and made threats to schools in the Denver metropolitan area.
The 18-year-old woman, Sol Pais, traveled to Colorado Monday night and is considered armed and dangerous, according to the Jefferson County Sheriff's Office.
Pais is about 5-foot-5, has brown hair and was last seen Monday night in the foothills of Jefferson County wearing a black T-shirt, camouflage pants and black boots, authorities said. She is allegedly "infatuated" with the Columbine shooting and traveled to Colorado and purchased a pump-action shotgun and ammunition.
Dean Phillips, special agent in charge of the Denver FBI, said a "massive" manhunt was ongoing Tuesday night and the woman had last been spotted in the foothills west of Denver.
The 20-year anniversary of the shooting is on Saturday.
All schools in the Denver metropolitan area were placed on lockout on Tuesday in response to the threats. Students were later released from class as normal, according to Jefferson County Public Schools. No students were injured and the lockout was a precaution recommended by the Colorado Department of Education.
Authorities announced late Tuesday they would be closing all Denver schools on Wednesday. Nearby public schools in Littleton, Cherry Creek, Aurora and Jefferson and Douglas counties will also be closed.
The threat is not isolated to one school or individual, police said.
Officials said Pais is from Miami and the Miami FBI notified Denver FBI about a threat Tuesday morning.
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