HIGHLANDS RANCH, Colo. — Douglas County School District Superintendent Liz Fagen said Wednesday a credible threat against Mountain Vista High School was for this week and a tip from a student made the difference in stopping it.

Fagen spoke one day after the Douglas County Sheriff’s Office announced two 16-year-old girls had been arrested in connection with the threat to the Highlands Ranch school and face pending charges of conspiracy to commit first-degree murder.

Douglas County has a program Safe2Tell and Text-A-Tip  and a tip was received Saturday as part of its multiple layers of security.

“No one safety strategy is guaranteed. We have to know that’s the case,” Fagen said.

Fagen could not release much detail about the threat and declined to say if it rose to the level of Sandy Hook or Columbine.

“Most of the time the threats are not found to be credible,” Fagen said. “This one was.”

Students at Mountain Vista are in finals on Wednesday. Fagen said a crisis team was on standby and there were increased patrols at the school.

“We know the gravity of what has happened in the past,” said Fagen, adding she feels confident in the safety at the school.

Detectives with the sheriff’s office are working with the 18th District Attorney’s Office and the Douglas County School School District to ensure the safety of all students.

Fagen said the district has received 231 tips from Text-A-Tip and 85 from Safe 2Tell this school year.

Anyone with information is asked to contact the sheriff’s office at 303-660-7500 or the major case tip line at 303-660-7579.

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