At least two people have been reported injured following what authorities are calling an "active shooter" situation at Arapahoe High School in Centennial, ColoArapahoe Sheriff Grayson Robinson told CNN that the shooter is still believed inside of the school, and CNN adds that all schools in the area have been placed on lockdown. 

We will update with more information as it becomes available.

UPDATE: The Associated Press is reporting that the suspect has been found dead, the victim of an apparent self-inflicted gunshot wound. 

[via CNN]