The incident occurred at the restaurant in the 200-block of West 26th Street at about 2:37 a.m.
Police said three suspects entered the restaurant which was closed at the time by breaking the glass on the front door.
The suspects were all armed with handguns and took cash from the register before fleeing the scene, police said.
Three female victims were inside the restaurant at the time and were not injured, police said.
No one is in custody and Area One detectives are investigating.
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