Shooting at Arapahoe High School in Colo.

Authorities are investigating a shooting at Arapahoe High School in Centennial, Colo.

An official said in a press conference Friday afternoon that the shooter is dead and another person is in critical condition in the hospital.

Colo. high school shooting

Arapahoe High School has more than 2,000 students and it is located about eight miles from Columbine High School, scene of a mass school shooting in 1999.

Colo. high school shooting

Students of Arapahoe High School had to evacuate the building after the shooting. 

Colo. high school shooting

There is an ongoing investigation. 

Colo. high school shooting

Police were outside the school, and students were seen walking toward the school's running track with their hands in the air. Television footage showed students being patted down.