An “anti-feminist” lawyer who allegedly killed a federal judge's son was found dead in the Hudson Valley.

Enter your number to get our free mobile app

Late Monday, the FBI identified Roy Den Hollander as the primary subject in the fatal shooting that occurred at the home of Judge Esther Salas on Sunday.

The FBI confirmed Hollander was found dead. Hollander was found dead from what's believed to be a self-inflicted gunshot wound on a property in Sullivan County, not far from Liberty, multiple media outlets are reporting, including ABC, NBC, and CNN.

Sources tell ABC News the dead suspect was a lawyer who had a case with Judge Salas in 2015. The dead body was found in a car by a municipal employee.  A FedEx package addressed to Salas was also found in the car, ABC reports.

On Sunday, someone potentially dressed as a FedEx delivery driver opened fire at Judge Esther Salas' North Brunswick home, NBC reports. FedEx said they are working with the police.

Salas was in her home's basement at the time of the shooting and wasn't injured. Her 20-year-old son, Daniel Anderl, was fatally shot and her 63-year-old husband, criminal attorney Mark Anderl, was also shot and critically wounded.

In 2011, Salas became New Jersey's first Latina US District Court judge after President Barack Obama nominated her and she was approved by the Senate.

According to the Associated Press, Hollander described himself as an “anti-feminist" lawyer who fought for “men’s rights.” He was previously best known for unsuccessful lawsuits that challenged the constitutionality of ladies' nights at bars, clubs and restaurants.

Judge Salas recently presided over a lawsuit filed by Hollander arguing against the U.S. military's men-only draft.

The FBI investigation remains ongoing. Individuals who believe they have information relevant to the investigation should contact FBI-Newark at 973-792-3000, press option 2.