Philadelphia's new district attorney fired 31 staffers Friday as part of a promised shakeup of an office tarnished by scandal.

DA Larry Krasner, 56, made the personnel moves on only his fourth day on the job.

Spokesman Ben Waxman said the changes shouldn’t be surprising, given that Krasner, a longtime civil rights lawyer, campaigned on a promise to clean up the DA’s office, which he previously called "off the rails," the Philadelphia Inquirer reported.

“Reorganization and a change in some key personnel are necessary to fulfill that promise,” Waxman said.

Krasner's campaign platform included reducing incarceration rates, ending cash bail and favoring lighter punishments for gun and drug offenders.

His disgraced predecessor, Seth Williams, was sentenced to five years in prison for accepting bribes.

Assistant DAs fired Friday included some veterans of the office.

The head of the Republican Party of Philadelphia said the firings were “what we might expect from a defense attorney who made a career out of suing the police. Krasner places victims on the back burner from day one.”

“Change is never easy," spokesman Waxner said. "But DA Krasner was given a clear mandate from the voters for transformational change.”