NEW YORK (AP) – The leader of a secretive group based in New York accused of branding female followers as part of an initiation ceremony has been charged with sex-trafficking.

Authorities say Keith Raniere was arrested in Mexico and brought to Texas Monday to face federal charges filed in Brooklyn. The leader of NXIVM was to appear in court Tuesday, officials said.

Raniere left the United States last year after The New York Times reported some women who joined a secret sorority within his Albany-based group were branded with a symbol that included his initials.

The women told investigators they were subjected to “master-slave” conditions that involved physical punishments for disobeying orders.

The name of Raniere’s attorney wasn’t immediately available. Raniere has claimed he wasn’t aware of the alleged abuses.