BOSTON ? A Lynn man and Hells Angels sergeant-at-arms was sentenced Tuesday to 21 years in prison for possessing a firearm and ammunition.Eric Franco, 38, of Lynn, was sentenced to 262 months in prison followed by two years of supervised release, Carmen Ortiz, U.S. Attorney for Massachusetts, announced Wednesday.The sentence comes from a 2011 incident.Lynn Police responded to Franco’s apartment on a report of an assault on May 3, 2011.A woman told police Franco grabbed her by the face and pinned her against a kitchen cabinet. She told police that Franco threatened to kill her and began throwing things around the apartment after she threatened to call police, The Daily Item previously reported.Police reported chasing Franco through Lynn Woods before finding him trying to hide under a rear deck on Pennybrook Road. Police found illegal and prescription drugs along with a weapon at the apartment, the Daily Item previously reported.Franco’s criminal record in Massachusetts includes three convictions for assault and battery with a dangerous weapon; as well as convictions for indecent assault and battery; failure to register as a sex offender; nighttime breaking-and-entering with intent to commit a felony; and conspiracy to violate the Controlled Substances Act, according to Ortiz.Franco was also convicted in Arkansas for second-degree battery in a case in which he and five other members of the Hells Angels assaulted and stabbed four members of another motorcycle club, according to the announcement. Franco served as the sergeant-at-arms of the Lynn Chapter of the Hells Angels, according to Ortiz.U.S. District Judge Denise Casper sentenced Franco Tuesday in Boston Federal Court.