VAN NUYS – Prosecutors backed away Wednesday from charging one of the two suspects arrested in the torching of an exotic dancer outside a Tarzana nightclub last week.

They declined to file against 22-year-old Nathaniel Petrillo “because there was insufficient evidence to prove he participated in the attack,” according to a statement from the Los Angeles County District Attorney’s Office.

But prosecutors filed charges of attempted murder, mayhem and torture against a 27-year-old Tarzana woman with a criminal record who pleaded not guilty Wednesday.

Trying to hide from a television pool camera, Rianne Celine Theriault-Odom [pictured] entered her plea in a barely audible voice as she appeared meekly behind a protective window in Van Nuys Superior Court.

Both Theriault-Odom and Petrillo were identified as suspects just hours after bikini dancer Roberta Abdue Dos Santos Busby was set on fire outside the Babes N’ Beer Sports Bar around 1:30 a.m. Feb. 5.

The two, targets of an intensive five-day manhunt, were arrested Monday at a Lankershim Boulevard motel in North Hollywood by police and U.S. marshals.

The decision not to charge Petrillo came around noon Wednesday, just hours before he and Theriault-Odom were both expected to be arraigned.

Prosecutors did not elaborate on what they considered insufficient evidence to charge Petrillo after police had initially named him as a suspect.

Theriault-Odom is charged with dousing Busby with a fire accelerant from a soda bottle and setting her ablaze.

Busby, a mother of two who lives in Simi Valley, suffered burns on 40 percent of her body and remains hospitalized in critical condition at the Grossman Burn Center in Sherman Oaks.

Police have not said what might have been the motive for the attack.

Superior Court Judge Thomas Rubinson set Feb. 24 for a preliminary hearing in the case against Theriault-Odom, as well as for a hearing on her violation of probation in a prior case.

Theriault-Odom, who remains in jail on $1 million bail, was convicted of burglary in November 2005.

If convicted in the attack against Busby, she potentially faces life in prison.

Although Petrillo was not charged, officials said he remains in jail because he violated his probation on a prior conviction.

He was convicted of drug possession in August 2008 and March 2007. He was also found guilty of credit card fraud in December 2006.

Petrillo had been released two weeks before the attack after serving a fraction of his one-year term for methamphetamine possession.

Police vice squad members and other city officials have mounted a campaign to permanently close the Babes N’ Beer club, which was cited two days before the attack for selling liquor without the proper licensing.

The club had become host to a range of alleged criminal activity, including prostitution, drugs and illegal alcohol sales, according to city officials, public records and bar employees.

City Councilman Dennis Zine waged a decade-long campaign to close the nude strip club, Frisky Kitty, that previously operated at the same location.