Colden Kimber, a 28-year-old San Francisco State University student and avid cyclist, was fatally stabbed on July 26, 2025, while protecting a mother and her two children from a stranger’s verbal aggression at a train stop. Witnesses say Colden quietly stepped between them, determined to shield the family, when the man suddenly attacked, stabbing him in the neck without warning.

The suspect, 29-year-old Sean Collins, has been charged with murder. Authorities are investigating, including a review of Collins’ mental health status, as the community reels from the senseless loss. Despite emergency aid, Colden did not survive his injuries.

Friends and coworkers described Colden as kind, generous, and deeply loved. Bradley Woehl, his employer at American Cyclery, recalled his positivity and dedication, calling him “totally irreplaceable as a worker and as a friend.” Tributes poured in from his cycling team and community, remembering him as a mentor and a bright, selfless presence.

To honor his memory, a memorial ride will be held in Golden Gate Park on September 7. Meanwhile, his family has launched a fundraiser to support memorial services and legal costs, which has already raised over $109,000. His mother, Lara, said his final act of courage reflected exactly who he was: “He would definitely do that without hesitation. I’m very proud of the person he grew into.”