Missing person: teenage boy in red hoodie

I last saw my 15-year-old brother, Lucas Rivera, yesterday around 3pm near the Cedar Rapids Public Library on 5th Ave SE. He’s about 5'6", with short brown hair, and was wearing a bright red zip-up hoodie, gray joggers, and white sneakers with a blue stripe. He was carrying a blue backpack with a panda keychain and has a small scab on his left knee from a skateboarding fall. He tends to walk toward the Riverwalk downtown, so he could be anywhere around downtown Cedar Rapids, including near the public library, the riverfront, or the bus depot. He has a medical condition that requires his daily meds, so we’re really worried and just want him back safe as soon as possible.