A 34-year-old man is in serious condition after he was stabbed on a CTA Red Line train Sunday morning.

According to Chicago police, the man was riding on a train near the 69th Street stop at approximately 2:51 a.m. when he got into a verbal altercation with another man.

During that altercation, the suspect pulled out a sharp object and stabbed the victim in the chest before fleeing the train, police said.

The victim was rushed to a nearby hospital, where he was listed in serious condition.

No suspects are in custody, and police are investigating the attack.