Police said a 22-year-old man and 23-year-old woman were outside the bar after working a concert at the space, which sometimes hosts concerts and live events, in the 1900-block of West Byron when four men got out of a dark colored sedan and flashed guns.
The armed men demanded the victims' property, and they handed it over, police said. During the robbery, police said the man was "struck about the head" with a gun. The woman was not injured.
The suspects fled in their vehicle. The man refused medical treatment at the scene, police said.
Martyrs' management confirmed the incident and said they are thankful "the two victims are not seriously hurt," but declined further comment.
No one is currently in custody. An investigation by Chicago police is ongoing.
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