Masked robbers wielding guns have struck several businesses in Prince George’s County since November, and investigators believe that the same group could be responsible for nine of the incidents, according to police.

Witnesses to the nine robberies describe a similar group: two or three men wearing black who come into the businesses in the evening, said Lt. William Alexander, a Prince George’s police spokesman. Their hoodies are up, they wear gloves or keep their hands in their pockets, and only their eyes show through their fabric face coverings.

“The styles of robbery are relatively close,” Alexander said. “They go in, they display a handgun, they demand money, they force the employee to open the register, they take the cash and then they flee.”

Although that is a common pattern among armed commercial robberies, Alexander said, detectives believe that the incidents are related based on details of witnesses’ descriptions of the criminals and surveillance videos at some of the businesses.

Police think the group has hit a Zips Dry Cleaners twice, the Glenn Dale Mini-Mart three times, a Subway and two pizzerias, Alexander said. All of the businesses are in the Lanham and Glenn Dale areas.

The robberies have not led to any injuries, but they have forced some business owners to take extra precautions to protect employees.

Vocelli Pizza, in the Lanham Shopping Center, was robbed Jan. 4.

“We’ve locked the front door at dusk, and we have a large sign that says, ‘Knock to enter,’ ” said the pizza shop’s owner, who asked to remain anonymous for his safety.

Police published surveillance video of the robbery at Vocelli this week, hoping that it will generate leads. The footage shows three men in black, with gloves and hoodies, entering the store. One points a gun at an employee, who then opens the cash register. One of the men stuffs his pockets with cash, and the three leave.

The robbers took about $150, the owner of the pizzeria said.

Police are working with other local law enforcement agencies to see whether the robbers have hit other jurisdictions but haven’t yet found evidence suggesting that they’re operating elsewhere, Alexander said.

“Keep your eyes out, and if you see anything suspicious, don’t be afraid to call and let the authorities know,” said the owner of the pizzeria robbed in January. “These guys probably walked about two blocks dressed in complete black with their hoods on, and you can’t see their faces. That should be suspicious.”

Because their faces were concealed by masks, the description of the robbers is vague. Witnesses have described the suspects as black men, all in their early 20s and anywhere from 5-foot-9 to 6 feet tall, Alexander said. All weigh around 150 pounds.

Police are asking anyone with information about the robberies to call 301-772-4905. To remain anonymous, call 1-866-411-TIPS.

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