A disturbing incident occurred on the Chicago transit system when a woman was set on fire during an argument aboard a CTA Blue Line train in the Loop. Witnesses reported that a man poured a flammable liquid on the victim before igniting it, leading to her hospitalization. Authorities have taken a person of interest into custody, but a manhunt remains ongoing for the suspect involved in the attack. Passengers expressed shock and horror at the violent escalation of the quarrel, highlighting concerns over safety on public transportation.