The union representing Chicago Transit Authority rail workers is calling for stronger safety measures across the transit system after a janitor was fatally stabbed last week at the Damen/Lake Green Line station. Justin Mobley was killed after stepping in during an argument between a man and another CTA employee inside a station kiosk, prosecutors said. The union says workers need more support at stations it considers crime hot spots, including increased staffing, improved lighting and dedicated transit police rather than officers assigned through Chicago Police Department overtime. “Our members show up every day to serve the people of Chicago. They keep this city moving. They deserve to return home safely,” said Pennie McCoach, president of Amalgamated Transit Union Local 308, at a news conference Monday. “We have been sounding the alarm about safety for years.” Prosecutors allege that 37-year-old Chevazz Campbell jumped a turnstile at the station Thursday, argued with a CTA employee and then sprayed Mobley with mace and stabbed him in the neck. Campbell later turned himself in to police. A judge ordered him held during court proceedings; he is due back in court Wednesday. Prosecutors say Campbell was wearing an ankle monitor at the time of the attack. They said they had sought to end his probation at least four times because of curfew violations. The Cook County State’s Attorney and transit union leaders are calling on lawmakers to strengthen the state’s electronic-monitoring system. McCoach said workers at some locations are left to manage an entire station or bus route alone. She also called for expanded mental-health facilities and homeless services, saying people should not have to rely on CTA trains and buses for shelter. Campbell has at least 29 recorded offenses dating to his teenage years, prosecutors said, and previously served time for a 2018 stabbing. He has been charged in Mobley’s killing; the allegations have not been proven in court.