NORTH BRUNSWICK, N.J. (CBSNewYork) — The gunman suspected of ambushing a federal judge’s family inside their New Jersey home has been found dead, sources tell CBS2.

He was discovered with an apparent self-inflicted gunshot wound outside a vehicle in Liberty, N.Y.

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The suspect was identified as Roy Den Hollander, 72, an attorney who had a case before the judge in 2015, law enforcement sources told CBS2’s Christina Fan on Monday.

The fatal ambush unfolded Sunday afternoon at Judge Esther Salas’ home on Point of Woods Drive in North Brunswick.

The judge’s husband is in critical condition, and the couple’s 20-year-old son is dead.

Investigators said Hollander wore a FedEx uniform and face mask to pose as a delivery driver and shot the judge’s husband — defense attorney Mark Anderl — as he answered the door.

Daniel Anderl, 20-year-old son of federal Judge Esther Salas, was shot to death inside their North Brunswick home.

Family friends said the couple’s son, Daniel Anderl, was killed when he ran to his father’s aid.

“I’m thinking maybe another kid would hide in a closet. I mean, you hear gunshots, you’d get scared, you don’t know what to do,” neighbor Marion Costanza said. “This kid just ran to help his dad, and I really can believe that. They were very close.”

Daniel graduated from Saint Joseph High School in Metuchen, and friends said he was pursing a law career at Catholic University in Washington.

The school held a virtual memorial Mass in his honor Monday night.

Also Monday night, grieving neighbors dropped off flowers on the family’s front lawn.

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“He was a loving, wonderful son — the only child, who wanted to be a lawyer like his parents,” said Costanza.

“Whole life ahead of him. He had two more years left of college, and it would have been cool to see what he can do, you know,” friend Joseph Mauro added. “Just a whole future ahead of this poor kid. I feel sorry for him.”

Sources told CBS2 Judge Salas was in the basement at the time of the shooting and was not injured.

She is seated in Newark and, according to the Associated Press, is presiding over a lawsuit in which Deutsche Bank investors assert the bank made false statements about its anti-money laundering policies and didn’t keep tabs on high-risk customers, like Jeffrey Epstein.

Neighbors described hearing several gunshots as they looked out their windows and saw what appeared to be a delivery truck parked in front of the house.

“I heard the gunshots. They were very loud. It’s like at least twice, maybe three times,” Wen Feng Zhang said. “Kind of horrifying. I never thought it would happen in my neighborhood. Usually, it’s very quiet.”

“They are really nice people. When we see each other, we always wave to each other,” Jenny Wang added.

“Just here out of empathy. I mean, it’s so sad,” Al LaGratta added.

Investigators believe the attack was very well planned. They’re looking through Judge Salas’ previous cases in search of a motive.

Hollander, a self-proclaimed men’s rights activist with a passion for the anti-feminist agenda, frequently posted videos to his YouTube page. In one that has since been taken down, he talks about bringing a lawsuit against clubs that give discounts to women on ladies nights, CBS2’s Jessica Layton reported.

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Investigators said there was a package inside the suspect’s vehicle addressed to the judge. At this point, it’s still unclear if the Salas or her husband were the intended target.