Chief Judge Freda Wolfson told CNN late Sunday that Salas' son Daniel Anderl, 20, was killed in the shooting and her husband, Mark Anderl, a defense attorney, was injured. Salas was unharmed, Wolfson said.

Both the US Marshals and FBI are investigating the shooting. Initial reports from law enforcement said Daniel Anderl opened the door with his father right behind him. The door opened to a hail of gunfire and the gunman fled, a law enforcement source told CNN.

"We are looking for one subject," the FBI said in a statement. "We are working closely with our state and local partners and will provide additional updates when available."

The gunman appeared to be wearing a FedEx uniform, a law enforcement official with direct knowledge of the investigation told CNN.

It is not yet known whether the gunman was a FedEx employee or someone posing to be an employee.

"We are aware of the media reports and are fully cooperating with investigating authorities," Jonathan Lyons, a spokesman for FedEx, said in an email statement.

Law enforcement has not been aware of any threats against the judge, the source told CNN. Right now investigators don't know the motive.

Federal court records show that Salas has presided over several high-profiles cases, including the financial fraud case of Real Housewives of New Jersey stars Teresa and Joe Giudice.

She also handled the 2018 sentencing of Farad Roland, who was found guilty of federal racketeering charges and sentenced to 45 years in prison by Salas. Roland was the leader of the South Side Cartel, "one of Newark's most violent street gangs," a press release from the US Justice Department said.

On Thursday, Salas was assigned to handle a class action lawsuit brought against Deutsche Bank by Ali Karimi on behalf of investors who purchased securities from the bank between November 7, 2017, and July 6, 2020. The complaint alleges that the bank "failed to properly monitor customers that the Bank itself deemed to be high risk, including, among others, the convicted sex offender Jeffrey Epstein," federal court records show.

Condolences for the judge and her family have come from top political leaders in New Jersey.

"Judge Salas and her family are in our thoughts at this time as they cope with this senseless act," New Jersey Gov. Phil Murphy said in a statement. "This tragedy is our latest reminder that gun violence remains a crisis in our country and that our work to make every community safer isn't done."

Democratic US Sen. Bob Menendez, who said he was proud to have recommended Judge Salas to former President Barack Obama, also issued a statement sending his prayers to the family.

"My prayers are with Judge Salas and her family, and that those responsible for this horrendous act are swiftly apprehended and brought to justice," Menendez said.

North Brunswick Mayor Francis "Mac" Womack told CNN over the phone Sunday night that Judge Salas' husband Mark Anderl is "one of the most straight-up honest attorneys" h