HIGHLANDS RANCH, Colo. (CBS4) – Authorities in Douglas County are investigating after some type of chemical device ruptured at SkyView Academy Tuesday morning.

The Douglas County Sheriff’s Office, Littleton Fire Department and South Metro Fire Department were on scene at the school trying to determine if it was a malicious or accidental event.

Students are still at the school but parents are being asked to pick them up at the SkyView Academy gymnasium.

Sgt. Ron Hanavan with the Douglas County Sheriff’s Office said nine patients were being evaluated. Five patients have been transported to an area hospital as a precaution; four students and one teacher.

CBS4 spoke with a student who had to be evacuated.

“I don’t exactly know. I guess some high schooler mixed chemicals or something and a gas spilled. I don’t exactly know yet, though,” the student said.

SkyView Academy is a Douglas County charter school located in the 6100 black Business Center Drive in Highlands Ranch.