The FBI Denver Division and the Jefferson County Sheriff's Office identified the woman as 18 year-old Sol Pais, who, according to CNN, allegedly “made threats in the Denver metropolitan area.”
The sheriff's office said in a Facebook post that the threats were “credible but not specific” and did not target any school in particular.
"It's a credible threat… but she did not make it directly," said Jenny Fulton, a spokeswoman with the sheriff's office. "There may be some connection to Columbine but it wasn't a specific directed threat towards Columbine."
Earlier on Tuesday, the Colorado Department of Education recommended that Denver area schools conduct a "lockout" after receiving the threats.
"We will have extra safety and security staff on site at all schools affected," Jefferson County Public Schools said in a statement.
Aurora Public Schools, east of Denver, said all of its schools were "placed in secure perimeter adding that the schools “have no info about a specific threat related to any schools in APS.”
Colorado schools have remained on high alert of a possible gun attack since April 20, 1999, when two students killed 12 students and one teacher in a mass shooting at Columbine. The two shooters took their lives in the school's library.=