Milton Deputy Police Chief Paul Nolan said William Donovan, 35, used a threatening note to rob a Citizens Bank branch in Milton and fled the scene on his red Vespa, the Boston Herald reported Friday.
Nolan said Donovan started by driving the wrong way on Granite Avenue and merged onto the Southeast Expressway before getting off at the first exit, taking him back to Granite Avenue.
"The guy wasn't a rocket scientist, taking off on a Vespa down the Southeast Expressway," Nolan said.
Boston police spotted the red motor scooter and cornered the suspect behind a business.
Officials said he was arrested on suspicion of bank robbery as well as a citation for riding his Vespa without a helmet.
Nolan said investigators are looking into whether Donovan was connected with another robbery at a Citizen's Bank branch in Quincy, Mass. He was being held in lieu of $65,000 bail.