The Boston Police Department reports a 71-year-old clerk at Hermanos Unidos, 728 Dudley St.  was shot to death around 10:30 a.m. on Sunday morning.
The police say witnesses saw two men go into the shop and that "once inside, weapons were displayed and money was demanded."
One of the men was dressed in all black, including a black hoodie. The other wore a red hoodie, police say.
The victim was taken to Boston Medical Center, where he was pronounced dead.
Anybody with information can contact the homicide unit at (617) 343-4470 or the anonymous tip line by calling (800) 494-TIPS or texting TIP to CRIME (27463).