A report of suspicious activity near Central High School on Tuesday, which sent the school into a shelter in place, involved a replica firearm, officials said.

Mesa County Sheriff's Office spokeswoman Megan Terlecky said at 12:40 p.m. the school received a report of two juveniles seen with a gun in a car near Long Family Memorial Park. The witness called 911 and a Central High School school resource officer responded.

Terlecky said the vehicle was located a short time later nearby on Hoover Drive. Two juveniles were detained and a replica gun was found, she added.

Terlecky praised the person who called in after what turned out to be something of a false alarm.

"I strongly encourage people who see something suspicious, who see something out of place to not hesitate to call 911," she said.

She said the Sheriff's Office takes the safety and security of the students and staff seriously and all real or perceived incidents are investigated, especially when there is an alleged gun involved.

According to the MCSO, the shelter in place was lifted within 20 minutes.

Mesa County School Resource Officer Supervisor Justin Montover said their top priority is  safety.

He said, in this incident, the last known location of the suspects was within 100 yards of the school and due to the proximity they elected to go into shelter in place.

"Once we have determined that all known threats have essentially been secured and everyone involved has been detained [the shelter is lifted]," he said. "Shelters and lockdowns are all about rather being safe than sorry."

According to the Mesa County Valley School District 51, a shelter in place is appropriate in situations that might not have the potential risk to students or staff for harm or injury, and still allows students to be kept in their assigned classrooms.

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