"A number of the 50 persons [who were canceled by Spoofcard] were making unauthorized entrances to Miss Lohan's voice mail." A source close to the scandal also told TMZ that Nicky Hilton and Paris' ex-boyfriend Stavros Niarchos may have been involved.

TMZ contacted Leslie Sloane Zelnick, rep for Lindsay, who would only say "I have turned this matter over to Lindsay's lawyers."

Hilton's rep, Elliot Mintz, told E! Online that what Del Bianco said with regard to his client "just didn't happen" and, at this point, he can't confirm whether the "Stars Are Blind" singer--who has been in Japan promoting her new album, Paris--is aware that she has a SpoofCard.com account at all.

"There are so many variables," Mintz said, adding that even if there is an account in Hilton's name, it doesn't necessarily mean she uses it or that she even opened it herself.

Earlier this montj, "Mean Girls" star Lindsay Lohan slammed her arch rival Paris Hilton with a thinly veiled attack about her infamous sex tape following the series of prank calls.

She told Elle magazine: "I started getting prank calls from people on my voicemail. They'd be screaming and saying stuff that was said in the 'fire crotch' video.

"Obviously Paris is very comfortable making videos.