Two suspects are in custody in the shooting at the STEM School in Highlands Ranch, a suburb of Denver which covers K through 12th grade.
Authorities say at least seven, possibly eight victims were injured in the incident that started in the middle school just before 2 p.m.,
Police and sheriff’s deputies were on the scene almost immediately and as they arrived at the school they could still hear gunshots.
Officials don’t know at this point if the suspected shooters were students.
The STEM School has about 1,800 students and is located about seven miles from Columbine High School, which is located in Littleton, Colorado.