Sporting a motorcycle helmet, an armed robber struck a bank in Farmington and fled on his two-wheel  getaway vehicle, authorities said.

The heist occurred late Friday morning at the Premier Bank on Oak Street, police said.

Along with the helmet, the suspect was dressed in all black, dark sunglasses and had a bandana wrapped around the lower half of his face, police added.

He left the bank on what may have been a Harley-Davidson motorcycle, heading east on Oak and then north on 4th Street, police said.Authorities did not disclose the amount of cash he stole.

pwalsh@startribune.com -- 612-673-4482