All schools in Denver should conduct a "lockout" and controlled release, according to a later tweet from the Colorado Department of Education.
This is after the FBI recognizes an individual who has made a convincing threat to schools, tweet said.
Jefferson County school officials tweet that all students and staff are safe and the students will be released on a normal schedule. "We will have additional safety and security staff on the site in all affected schools," said Jefferson County Public School.
Columbine High at Littleton and some of the schools in the area were earlier placed in a "lockout," the Jefferson County Sheriff & # 39 ; s Office has tweeted. The threats are not taught in a particular school, according to sheriff spokesman Mike Taplin.
Another sheriff spokeswoman Jenny Fulton told the FBI that the threat was evident.
Aurora Public Schools, east of Denver, schools are "placed in a safe perimeter." The city police provided more security while releasing students, the district's tweet. "We have no information about a particular threat associated with any APS schools."
Nearly 20 years ago, two students, Dylan Klebold, 17, and Eric Harris, 18, murdered 12 students and a teacher in a mass shooting at Columbine. Two shooters took their life at the school's library.
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