A Nxivm cult member who secretly pleaded guilty last week to charges of racketeering conspiracy admitted to keeping her own personal slave locked in a room for two years, newly unsealed court documents reveal.

“I knowingly and intentionally harbored Jane Doe 4, a woman whose identity is known to me, in a room in the home in the Northern District of New York,” said Lauren Salzman to Brooklyn federal court Judge Nicholas Garaufis last week.

Salzman told the judge she held the woman hostage between March 2010 and April 2012 “and threatened to deport Jane Doe 4 back to Mexico if she did not complete labor requested by myself and others,” court transcripts said.

The 42-year-old defendant also admitted during the proceeding to being a member of Nxivm’s secret inner organization, DOS, which prosecutors have accused of starving and branding women.

At least one DOS member was also coerced into having sex with cult leader Keith Raniere, according to the government.