Thousands of runners are participating in a 5K race to honor the memory of a Massachusetts high school teacher who was killed last October.
Runners gathered Sunday in Andover for the Step Up for Colleen 5K to remember Colleen Ritzer. She was a math teacher who was found slain behind Danvers High School.
Her family released a video thanking supporters for their support.
Participants included students and teachers from Danvers and Amesbury and from Sanborn Elementary School in Andover that Ritzer attended as a girl.
Her roommates and friends from Assumption College in Worcester, where she earned her teaching degree, also are participating.
A high school student, Philip Chism, has been charged with first-degree murder, rape and robbery. He was 14 at the time.
Chism has pleaded not guilty.