It happened near the 800 block of Aquahart Road in Glen Burnie around 5:40 p.m. on Friday, March 29.
The 54-year-old victim had arranged to meet with the suspect, a white male, to conduct a sale, police said.
When the victim handed the suspect the item, the suspect "got into a gold sedan, pointed a handgun at the victim, and drove off without paying," police said.
The investigation is being led by Northern District detectives. Anyone with information is asked to contact 410-222-6135 or the Tip Line at 410-222-4700.
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