Columbine honors 13 lost with community service, ceremony

Sixteen-year-old Maren Strother of Denver looks over the plaques for the victims of the Columbine High School massacre on Friday in Littleton, Colo. (AP Photo/David Zalubowski)

LITTLETON, Colo. — Community members in suburban Denver marked the 20th anniversary of the Columbine High School shooting Saturday by cleaning neighborhoods, volunteering at shelters, placing flowers at a memorial and attending a remembrance ceremony.