*** UPDATE 3:54 pm ***
Arapahoe Sheriff Grayson Robinson says that they have found the person believed to be the shooter, dead of an apparent self-inflicted gun-shot wound.
The Sheriff says that the shooter entered the building announcing the shooter's intent to shoot a teacher. The teacher was able to leave the building safely.
A hospital spokesman says a student is in critical condition after reports of a shooting at a school in suburban Denver.
Jason Dunkel, spokesman for Littleton Adventist Hospital, says the student was in surgery Friday. It's unclear how the student was wounded.
*** END UPDATE ***
Colorado emergency officials say police are responding to a report of a shooting at a high school in suburban Denver.
State division of emergency management spokeswoman Micki Trost said Friday that her director went to Arapahoe High School in Centennial. There weren't any more immediate details.
Police were outside the school, and students were seen milling around on sidewalks.
The school is about 8 miles east of Columbine High School in Littleton, where two teenage shooters killed 12 classmates and a teacher before killing themselves in 1999.