A Westbrook woman was sentenced to more than four years in prison for her role as getaway driver in a string of bank robberies, including one in Lewiston.

Maria Mattson, 31, was sentenced in U.S. District Court in Portland to 50 months in prison followed by three years of supervised release for aiding and abetting bank robbery, conspiracy to commit bank robbery and aiding and abetting interference with commerce by robbery. She pleaded guilty to those charges Aug. 1, authorities said.

Mattson served as getaway driver for robberies of two credit unions in Portland, one in Windham and the Auburn Savings Bank in Lewiston during January and February. She also was getaway driver for the robbery of a Cumberland Farms in Portland during that time.

The charges resulted from a collaborative investigation conducted by police in Lewiston, Portland and Windham, police said. Also involved was the Southern Maine Gang Task Force, which is comprised of investigators from the Federal Bureau of Investigation, Portland police, the federal Department of Homeland Security, Homeland Security Investigations, the Bureau of Alcohol, Tobacco, Firearms and Explosives, and the federal Drug Enforcement Administration.

Mattson and co-defendant Paul Sans, 30, of Westbrook were arrested on Feb. 15. He pleaded guilty in October to several counts of bank robbery.