Boston Mayor Michelle Wu responded to criticism she received after giving her condolences to the family of a person police say was wielding a knife when he was shot and killed by an off-duty officer.

Wu has won their backing after successful contract negotiations. The endorsement comes as the mayor prepares to testify in Washington over what Republican legislators call the city's "sanctuary" policies.

Boston’s largest police officers' union will endorse incumbent Mayor Michelle Wu for reelection on Thursday afternoon, its leadership said. The Boston Police Patrolmen’s Association said its members voted “overwhelmingly” to support Wu at the union’s most recent monthly meeting.