The attacker initially stayed on the scene, but later left on a MARTA bus, police said.
When officers arrived, they found the 35-year-old victim unconscious outside room No. 320.
He was taken to Grady Memorial Hospital, where he died, Robertson said.
The attacker is about 5-foot-10 and 250 pounds, police said. He is bald, has a beard and was wearing a camouflage shirt with black pants, Robertson said. Police do not believe he is armed.
It is unclear if he and the victim knew each other.
MARTA’s deputy police chief is overseeing efforts to help find the man, the agency said.
Meanwhile, officers are going through surveillance video of the fight.
— Please return to AJC.com for updates.
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In other news:
The airport says there are no injuries reported.