The incident occurred at the 900 block of 18th Avenue just before 3:15 p.m. Thursday afternoon, according to officials.
They say the group of males wearing masks and armed with handguns entered the establishment demanding cash.
One victim was placed face down with a gun to the back of his head as one of the men went through his pockets. A second victim was held at gunpoint in the lobby of the building, while an employee was struck with a handgun.
The injured victim was transported to University Hospital and is in stable condition.
The group was last seen on 18th Avenue with stolen cash and personal property.
Anyone with information regarding the identity of either of these suspects is to call the Newark Police Division's 24-hour Crime Stopper tip line at 1-877-NWK-TIPS (1-877-695-8477). All calls are kept confidential and could result in a reward.
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