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HIGHLANDS RANCH, Colo. — Two 16-year-old girls have been arrested after a credible threat was made to Mountain Vista High School, the Douglas County Sheriff’s Office said Tuesday.

On Saturday, the sheriff’s office said it was made aware of the threat at the Highlands Ranch school. Investigators determined it was a credible threat and led to the arrest of the girls.

The 16-year-olds have been arrested and face pending charges of conspiracy to commit first-degree murder.

“We take these types of threats extremely seriously and will take all efforts necessary to ensure the safety of our schools, students, and teachers,” Douglas County Sheriff Tony Spurlock said in a news release.

No details of the plot were released. Detectives are working with the 18th District Attorney’s Office and the Douglas County School School District to ensure the safety of all students.

“At this time we believe the situation has been contained and the threat disrupted,” the sheriff’s office said in a news release.

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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