According to the Douglas County Sheriff's Office (DCSO), authorities have arrested two suspects that are both male students. One individual was identified as a juvenile, and the second is an adult.
The sheriff's office also noted that the pair were confronted by officers "right away," stressing that the "quick response helped save lives."
The shooting occurred at STEM School Highlands Ranch, a public charter school with more than 1,850 students in kindergarten through 12th grades, AP reports. Police responded to the incident at about 1:50 p.m. local time.
The sheriff's office has directed parents to a recreational center to pick up their children.