Sienna Johnson is a 16 year old from Douglas County, Colorado.
Johnson is one of two students accused of planning an attack on fellow students at Mountain Vista High School in Highlands Ranch, Colorado. The town is about 20 miles south of Denver.
Prosecutors described Johnson as “extremely violent.” Reports indicate that Johnson bought a BB-gun to target practice and had harmed her pets with the weapon.
Another girl is accused along with Johnson of planning the attack.
Authorities were tipped off about the planned attack via a tip line that had been set up in the school system.
Sienna Johnson Photos