Student Shot at High School Outside Denver
PHOTO: Students are seen outside Arapahoe High School in Centennial, Colo. on Dec. 13, 2013 where a  shooting has been reported.

A student who walked into his suburban Denver high school with a shotgun looking for a specific teacher was a skilled debater with strong political views who recently was kicked off the speech and debate team.

Eighteen-year-old Karl Pierson critically wounded one student before apparently killing himself Friday at Arapahoe High School as police moved in.

Steve Miles is an English teacher who taught Pierson as a freshman. He says the school librarian who ran the speech team cut Pierson from the team, but he didn't know why.

Authorities haven't identified Pierson's target, but students say it was the librarian.

Fellow students describe Pierson as outspoken and smart — not a loner. They also say he held communist views.

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