By George P. Hassett

Police are looking for a man they say robbed the Citizens Bank in Davis Square Saturday morning.

The suspect is described by police as a white male in his 30s about five foot nine, with brown hair and a medium build. Police said he stopped in the foyer area before walking into the bank and pulled up his jacket or shirt to cover his face. He then entered the bank and walked behind a customer in line, they said.

He allegedly handed the teller a white plastic bag. The bank employee gave the bag back with cash in it, police said. The suspect fled the bank onto Elm Street. He was wearing a blue baseball cap and faded blue jeans. Somerville detectives and the FBI Bank Robbery Task Force are investigating.