CTA janitor Julian Mobley, 41, died after he was stabbed during an argument at the Damen Green Line station on Chicago’s Near West Side on Thursday afternoon, police said.

Another man approached Mobley at the station in the 2000 block of West Lake Street around 3 p.m., according to Chicago police and ATU Local 308, which represents him. The dispute turned physical, and the man stabbed Mobley in the neck with a sharp object. Mobley was pronounced dead at Stroger Hospital.

Police said the man fled west. No one was in custody, and detectives were investigating. Green Line trains bypassed Damen during the evening, with service restored around 8 p.m. The CTA said it was working to share footage of the attack with investigators.

Union president Pennie McCoach said Mobley had belonged to Local 308 since 2018 and was a father of two. She called for a review of worker safety protocols, more security and better training.