ATLANTA -- Atlanta police said a man was stabbed at Piedmont Park Saturday morning.

Investigators said two men got into an altercation near a lake inside the park at about 3: 30 a.m.

Police said the perpetrator punched the victim twice and then stabbed him twice in the stomach.

Authorities said it was unclear if the victim knew the perpetrator.

The victim was taken to Grady Hospital, where he was listed in critical condition at last check. He was expected to undergo surgery.

Police described the perpetrator as a black male, between 5 feet 4 inches and 5 feet 6 inches tall, carrying a backpack.

Authorities said the perpetrator was last seen running toward Piedmont Avenue.