Fe​deral authorities have busted four more people for their alleged roles in upstate sex cult Nxivm​ ​– including Seagram’s liquor heiress Clare Bronfman.

The cult’s co-founder Nancy Salzman and her daughter, Lauren, were arrested​ upstate, as was Kathy Russel, a longtime bookkeeper for the shady organization that bills itself as a self-help group.

All four women are expected to be arraigned on charges of racketeering conspiracy later Tuesday​ in Albany and Brooklyn federal courts​.

The arrests are part of an ongoing federal investigation into the group, its leader Keith Raniere and his right hand woman, former ​”Smallville​”​ star Allison Mack.

Raniere and Mack are charged with sex trafficking and conspiracy for allegedly coercing women into joining a secretive master-slave group within NXIVM — where “slaves” were forced to pleasure Raniere, have his initials permanently branded onto their skin and perform free labor.

Bronfman — who used her fortune to bankroll the group — Russel and Nancy Salzman are variously accused of participating in identity theft, money laundering, and altering records to facilitate the enterprise.

Lauren Salzman — who’s been accused by former “slaves” of being one of the “masters” in the group — is alleged to have committed forced labor, extortion and wire fraud.

Raniere, a former Amway salesman and multi-level marketing schemer, founded Nxivm — originally called Executive Success Program — in the late 1990s with Nancy Salzman, a nurse trained in hypnosis and neurolinguistic programming.

Members of the group — which ostensibly runs personal and professional development workshops — call Raniere “Vanguard and Nancy “Prefect.”

In 2007, Nancy Salzman created a non-profit within Nxivm called the Ethical Science Foundation, which was being probed by the state attorney general for doing bizarre brain-activity studies with no oversight.

That probe has been suspended for the federal case, according to the Albany Times Union.

From the beginning of Nxivm, prosecutors allege that Raniere kept “a rotating group of 15 to 20 women” from the group as his personal harem — and gradually introduced his perverse ideas into the organization, including sessions where women “wear fake cow udders over their breasts while people called them derogatory names.”

But in 2015, things got seriously twisted when he created a secret master-slave “sorority” within Nxivm called “The Vow,” prosecutors allege.

When slaves went public with their experiences last year and the feds started closing in, Raniere fled to a luxury villa in Mexico with the help of Bronfman’s money, prosecutors allege.

Raniere was arrested there in March, and Mack was collared a month later.

In a now-deleted post on one of the group’s websites, Bronfman defended Raniere and said that, while she was not a member of the Vow, it “has not coerced nor abused anyone.”

“In fact, the sorority has truly benefited the lives of its members, and does so freely. I find no fault in a group of women (or men for that matter) freely taking a vow of loyalty and friendship with one another to feel safe while pushing back against the fears that have stifled their personal and professional growth,” she wrote.

Bronfman faces 20 years behind bars and has hired high-powered lawyer Susan Necheles to represent her.

Necheles didn’t immediately return a request for comment.

Russell’s lawyer declined to comment. Nancy Salzman’s lawyer couldn’t be immediately reached for comment.