The spokesperson could not confirm whether Mack had been released as of Tuesday afternoon. The actress was later seen leaving jail, according to media reports.Mack will be under house arrest in California and must wear an electronic monitoring device, the official added. Mack's attorneys have not responded to CNN's request for comment. Mack's approved release comes on the same day it came to light that her attorneys are in the process of negotiating a possible plea deal with prosecutors, according to public filings. The documents, signed by a judge last week and obtained by CNN, indicate a "reasonable likelihood" that the plea negotiations will "result in a disposition of this case without trial." Mack was indicted last week on charges of sex trafficking, sex trafficking conspiracy and forced labor conspiracy, according to a statement released by the Justice Department.Mack's charges relate to her alleged involvement with an organization called Nxivm (pronounced NEX-ium), an Albany, New York-based group that claimed to be a self-help program but was, in reality, a pyramid scheme in which some recruits were exploited sexually and for their labor,prosecutors allege in court filings. Mack pleaded not guilty.As part of her release, Mack is prohibited from contacting or associating with any present or former members of Nxivm, the U.S. Attorney's Office official told CNN.Nxivm's founder, Keith Raniere, also known within the group as Vanguard, is also fighting charges.Mack, 35, is professionally best known for her role as Clark Kent's confidant Chloe Sullivan on CW's "Smallville," which ran for 10 seasons. The allegations made against Mack and Raniere stem from what officials say were activities that took place as part of a secret society within Nxivm called "DOS," in which women recruited others under false pretenses to perform sexual acts. Women who successfully recruited were called "masters" within the group, while others were referred to as "slaves."The indictment claims many so-called slaves were branded on their pelvic areas with a symbol which, unbeknownst to them, incorporated Raniere's initials.Raniere was the only male in DOS and the leader, according to court filings.Raniere's attorneys have not responded to CNN's request for comment.A statement posted on the homepage for the Nxivm website says the group is "working with the authorities to demonstrate [Raniere's] innocence and true character.""We strongly believe the justice system will prevail in bringing the truth to light," the statement reads.If convicted of the crimes charged, Raniere and Mack each face mandatory minimum sentences of 15 years imprisonment, and up to life imprisonment.