It happened about 3:30 p.m. on the 3100 block of North Market Street.
Police say the victim was walking down the block when a masked man with a handgun confronted him.
The suspect demanded the victim's property. The victim complied and gave his cellphone to the robber, who then fled.
The suspect is described as 25 to 26 years old, 5 feet 8 inches, and was last seen wearing a camouflage hooded sweatshirt, tan pants, and a dark mask.
Anyone with information can call Wilmington Police or Delaware CrimeStoppers.
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