Following the release of several nude images on 4chan Sunday night, Jennifer Lawrence's attorney is already hard at work attempting to remove the risqué shots from the Web. Unfortunately for the 24-year-old film star, one porn site featuring the images is now fighting back against a request to remove the illegally obtained photos.

“The site’s stance is since some of the pics are NOT selfies, the person who actually took those photos would most likely hold the copyright,” reported TMZ. The unidentified adult content provider is now reportedly demanding Lawrence’s attorney prove her ownership of the non-selfie pictures or reveal the name of the individual who took the images.

Lawrence’s legal snag comes three days after she confirmed she would be pursuing legal action against the individuals responsible for obtaining and publishing the authentic and personal shots. “This is a flagrant violation of privacy,” a spokesperson for Lawrence said in a statement to the Hollywood Reporter. “The authorities have been contacted and will prosecute anyone who posts the stolen photos of Jennifer Lawrence.”

The FBI confirmed its involvement in the investigation Monday. “The FBI is aware of the allegations concerning computer intrusions and the unlawful release of material involving high profile individuals," spokeswoman Laura Eimiller told the Los Angeles Times, adding that the bureau is "addressing the matter."