Investigators said it happened a bit before 2 a.m. at the Wendy's along the 900 block of Cottman Avenue in the city's Burholme section.
Police are telling Action News the man hid in the bushes outside the Wendy's and then ambushed the manager.
"One of the employees was outside of the business putting out the trash and cleaning up, and she was approached by a lone actor with a handgun, forcing her into the office," Capt. John Ryan.
Officers said he put the 25-year-old manager in a headlock, and pistol-whipped her in the head and face with the gun.
The man then pulled the manager back into the restaurant where four other employees were waiting on rides, police said.
That is when the attacker allegedly started demanding money while threatening to harm the manager.
The attacker ended up leaving empty-handed after realizing the registers had already been emptied.
Police said the man then left.
The pistol-whipped manager suffered, relatively minor injuries, no one else was injured.
Now, Police are working to see if this case might be linked to other such cases nearby, including the robbery of a McDonald's in Lawncrest when a gun-wielding man jumped into the drive-thru window of the McDonald's along Adams Avenue.
"We had some similar robberies in the area over the past few months that may be the same person, because the MO are similar in a couple of those jobs. We have to take a closer look at it," Ryan said.
Police said the suspect was wearing all black, had on a hoodie, gloves and a black mask where you could only see his eyes.
Investigators are sorting through surveillance video from inside the Wendy's to hopefully get a better look at the suspect.
Anyone with information about this case is asked to contact Northeast Detectives.
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