A Massachusetts grand jury has indicted 12 current and two former officers of the Springfield Police Department who are accused of beating a group of four black men after a barroom dispute or participating in a cover-up of the assault.

The announcement by the state attorney general’s office and the F.B.I. on Wednesday is the latest blow to the police force in Springfield, the state’s third-largest city.

Last fall, two other police officers in the city were indicted on charges of using unreasonable force while arresting two Hispanic boys. They have pleaded not guilty. Additionally, the Justice Department is investigating whether the Springfield narcotics unit routinely used excessive force and violated residents’ civil rights.

Wednesday’s indictments stem from an April 2015 confrontation that began inside Nathan Bills Bar & Restaurant, when one of the black men whistled at a bartender to get her attention. One off-duty officer thought the man was whistling at his girlfriend, an officer who was also off duty at the time, according to a federal civil rights lawsuit brought by the four black men