It happened at 7:42 a.m. inside the fast-food restaurant on 7th Avenue at 34th Street.
The 53-year-old man was trying to place an order at a kiosk when the attacker suddenly punched him in the face and demanded his wallet.
The attack continued with the man punching and knocking the victim down.
While the victim was on the ground, the man kicked him in the head and robbed him of his cellphone and wallet.
The robber then ran off into Penn Station.
The victim sustained a severe head injury and is in critical but stable condition at NYC Health + Hospitals/ Bellevue.
The attacker is described as having a medium complexion, slim build, and was last seen wearing a black winter hat, a dark blue The North Face jacket with yellow trim, dark blue, gray and white pants, and brown boots.
Anyone with information in regard to this incident is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477) or for Spanish, 1-888-57-PISTA (74782).
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