A Chicago man was stabbed while on a Chicago Transit Authority train on Thursday afternoon, according to police.
The man, who police say is 42, sustained stab wounds to the upper left leg and lower back during the incident.
He was transported to Northwestern Hospital and is reportedly in critical condition, according to police.
At the time, the CTA said there were "significant delays" due to a police investigation.
"[Significant Delays] Forest Park-bound Blue Line trains are standing at Monroe due to police activity. Crews working to restore service," the CTA tweeted.
The incident comes after a string of crimes on CTA trains.
On June 16, a 21-year-old man was stabbed wile riding a Red Line train in Chicago's Englewood area, according to FOX 32. A suspect was arrested a short time later and a knife was found.
On June 21, a man was shot while he was on a Red Line train. The man allegedly got into an argument into another individual who then pulled out a gun and shot the man, according to FOX 32.
He was shot in the back and legs during the incident, which Chicago police say was caught on camera.
"The offender shoots at the victim and then the offender flees, making good his escape from the platform," Supt. David Brown said.