A law enforcement official says federal investigators are examining whether a suspect in the ambush shooting of a federal judge’s family in New Jersey is also responsible for the killing of a fellow men’s rights lawyer in San Bernardino County.

Roy Den Hollander, 69, is suspected of posing as a FedEx driver when he allegedly went to the North Brunswick, New Jersey, home of U.S. District Judge Esther Salas, and started shooting, wounding her husband, the defense lawyer Mark Anderl, and killing her 20-year-old son, Daniel Anderl.

Federal agents are trying to determine whether he had any role in the killing of attorney Marc Angelucci in Crestline earlier this month.

Angelucci was found shot to death at at a home 22400 Glenwood Drive around 4 p.m. on July 11.

“The way he was killed, it seemed like it was a hit. Someone wanted to silence him” Ronda Kennedy, a friend and associate of Angelucci, told KTLA.

In that case, the shooter also apparently posed as a delivery driver, the law enforcement official told the Associated Press.

Investigators are also examining Den Hollander’s financial and travel records, as well as misogynistic screeds he posted online, said the official, who could not discuss an ongoing investigation publicly and spoke to the AP on condition of anonymity.

The San Bernardino County sheriff’s department referred questions to the FBI.

Angelucci was a prominent figure in the non-profit National Coalition for Men, which describes itself as a gender inclusive and non-partisan organization that “has been committed to ending harmful discrimination and stereotypes against boys, men, their families and the women who love them” since its founding in 1977.

Den Hollander was a self-described “anti-feminist” lawyer who received media attention including appearances on Fox News and Comedy Central for lawsuits challenging perceived infringements of “men’s rights.”

He was found dead of an apparent self-inflicted gunshot on Monday in Sullivan County, New York, two officials with knowledge of the investigation told the AP.

Investigators found items in his possession that raised concerns about whether he had targeted, or planned to target, other people, including a photograph of New York Chief Judge Janet DiFiore and the address of a state appeals courthouse, a state court spokesperson said.

Both Den Hollander and Angelucci, 52, were involved in lawsuits seeking to force the U.S. government to require all young women to join men in registering for a possible military draft.

Den Hollander’s lawsuit, filed in 2015 on behalf of a woman in New Jersey, was assigned to Salas. He withdrew as the lawyer in the case a year ago after being diagnosed with cancer.

Harry Crouch, president of the National Coalition for Men, told The Associated Press that Den Hollander was furious that he hadn’t been involved in a similar case being handled by Angelucci.

“Roy was just not happy that we did not involve him as a co-counsel. I think unhappy is an understatement,” Crouch said. “He called me up and threatened me.”

Crouch said Den Hollander did not have a good reputation among other men’s rights advocates.

“I think he was very hostile, very, very hostile that he finally went over the hill,” Crouch said.

In more than 2,000 pages of often misogynistic, racist writings posted online, Den Hollander had sharply criticized Salas and other female judges.

He also wrote about wanting to use the rest of his time on earth to “even the score” with his perceived enemies, using “cowboy justice.”

J. Steven Svoboda, a spokesman for the National Coalition for Men who said he was speaking personally and not on behalf of the organization, said Angelucci was “beloved” for his “groundbreaking legal work all. in his mind, to make the world a better place.”