LITTLETON, COLO. (AP) -- Classes are canceled at Columbine High School in remembrance of those killed in the shootings at the school 12 years ago.

Twelve students and a teacher were killed in the shootings on April 20, 1999. The teenage gunmen committed suicide.

No events were planned at the school on Wednesday but a memorial to the victims in Clement Park near the school is open to the public.

A documentary about the different ways that families who lost loved ones in the shootings also premiered in the Denver area this week.

The film doesn't include pictures of Eric Harris and Dylan Klebold, reflecting frustration expressed by families at the attention focused on the gunmen.

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