California police are investigating the homicide of a well-known activist in the so-called men’s rights movement who was found shot to death at his home over the weekend.

Marc Angelucci was the founder of the Los Angeles chapter of the National Coalition for Men and the force behind many of the group’s lawsuits, and he was featured in the controversial documentary The Red Pill.

The San Bernardino County Sheriff’s Office said deputies responding to a reported shooting in Crestline on Saturday afternoon found the 52-year-old “unresponsive and suffering from apparent gunshot wounds,” and he was pronounced dead at the scene.

“The investigation is ongoing,” the sheriff’s office said. “The motive for the shooting is unknown at this time.”

The National Coalition for Men—which claims that women have more rights than men do—says Angelucci joined while he was in law school in 1997 after witnessing a male friend’s abuse by his wife. He then went on to sue battered woman’s shelters to force them to take in men.

“Marc was an unbelievably generous man, living on a shoestring despite some personal health challenges so he could donate many millions of dollars of his time to mostly voluntary legal work on behalf of men’s rights and the genuine gender equality that is so badly needed in this country and this world,” the group said in a statement after his death.

As The Daily Beast has reported, Angelucci volunteered his time with a law firm launched by the coalition in 2018 to solidify men’s rights through litigation. Last year, they won a major victory when a federal judge ruled the military’s men-only draft is unconstitutional—a decision under review by an appeals court.

“What’s happening now is we’re getting more and more people offering to help. More and more people are coming to us and finding us. People who watch The Red Pill are coming to us,” Angelucci said then.

The Red Pill, which premiered to protests, is a 2016 documentary by self-proclaimed feminist Cassie Jaye that critics said was overly sympathetic to the men’s rights movement. In a blog post, Jaye said he attended her wedding, and she last spoke to him on July 1.

“Although I’ve met so many wonderful people through making The Red Pill, there’s not very many I see eye-to-eye with 100% of the time, but I could always stand behind Marc 100% of the time,” she said. “He won so many cases that few would be willing to touch and fewer would be willing to do pro bono, but he did it because it was the right thing to do.”

The Southern Poverty Law Center has been critical of the National Coalition for Men’s efforts, writing that it and groups like it “distort or cherry-pick statistics to indicate female privilege, blame women, or create false equivalences between the oppression of men and of women, rather than simply seek to advance the cause of men and fathers.

“Groups like NCFM use litigation to challenge what they perceived as discrimination in favor of women and try to influence policy on domestic violence, sexual assault, divorce, and custody cases,” the SPLC added. “In reality, they offered little help to men other than blaming women or advocating to deny women the structures that they did have to resort to discrimination or violence.”