Barnstable police said the men, two of whom were carrying knives while the third was armed with a hatchet, entered the Dunkin' Donuts on West Main Street in Hyannis Wednesday night and demanded an employee hand over a paper bag they apparently believed to contain money, the Cape Cod Times reported Monday.
However, Sgt. Thomas Twomey said the bag, which the men did not open before leaving, contained doughnuts.
Police said they identified the men from security camera footage of the incident.
Nicholas Mercurio, 19, Lukas Peterson, 21, and Charles Iliffe, 20, were arrested and charged with armed robbery while masked.