Two men were arguing on a CTA Blue Line train Sunday morning when one of them pulled out a knife and swung at the other, according to Chicago police.
The argument happened around 6 a.m. in the 500 block of North Milwaukee Avenue near the Grand Avenue Blue Line stop, police said.
The man who swung the knife cut the other man on his hand. The man, 32, was taken to Humboldt Health Hospital in good condition.
No one is in custody, police said.