Authorities were investigating what appears to be a “credible threat” at Columbine High School and nearly 20 other schools, the Jefferson County Sheriff’s Office in Colorado said Tuesday.
School officials later tweeted that all students and staff are safe and students will be released on a normal schedule. “We will have extra safety and security staff on site at all schools affected,” Jefferson County Public Schools said.
Columbine High in Littleton and several schools in the area were earlier placed on a “lockout,” the Jefferson County Sheriff’s Office tweeted. Threats were not directed to a specific school, according to sheriff’s spokesperson Mike Taplin.
Jenny Fulton, another sheriff’s spokesperson, said the FBI is investigating the apparent threat.
Nearly 20 years ago, two students, Dylan Klebold, 17, and Eric Harris, 18, killed 12 students and one teacher in a mass shooting at Columbine. The two shooters took their lives in the school’s library.