Island Shoppers grocery at Jaegers Street, Plymouth, was robbed, of an undisclosed amount of cash, at gunpoint just before 4 pm on Tuesday.
According to an eyewitness report, two masked men walked into the grocery and announced a holdup.
“It happened so fast that no one realized what was happening,” one eyewitness told Guardian Media.
Just on Monday the Coco Reef Resort and Spa was robbed by two men armed with cutlasses.
They were later detained by police.
In December last year, armed bandits robbed security officers just outside the Penny Savers grocery.
Security officer Mark Nurse was shot dead during the robbery.