Roberto Santos-Melendez, 44, was found shot to death in the parking lot of the store in the 7700 block of 23rd Avenue around 1 a.m., Monday, Sept. 5, according to Prince George's County police.
Police are looking to identify a suspect and a motive for the crime.
A canvass will begin at 4 p.m. at 7701 23rd Avenue, police say.
A $25,000 reward is being offered for information leading to an arrest and indictment in this case.
If anyone has information relevant to this investigation, they are asked to please call detectives 301-516-2512.
Callers wishing to remain anonymous may call Crime Solvers at 1-866-411-TIPS (8477).
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