UNITED STATES -- The Arapahoe County Sheriff says the student who opened fire at Denver area high school is dead after turning the gun on himself.
Authorities say the gunman showed up at the high school carrying a shotgun.
The sheriff called it an active shooter-situation.
At least one student was shot and is listed in serious condition.
Another student was also hurt.
In a press conference the sheriff said school officials made a crucial move that likely prevented a greater tragedy.
"The gunman came into the school and immediately asked for the location of a very specific teacher and he named that teacher by name. When the teacher heard that this individual was asking for him, the teacher exited the school immediately. In my opinion, was the most important tactical decision that could have been made," said Grayson Robinson, Arapahoe County Sheriff.
Arapahoe High School is in suburban Denver and is in a neighboring Town of Littleton, Colorado.
Littleton is where the Columbine shootings happened back in 1999.