Authorities are investigating whether two Las Vegas nightclubs let Paris Hilton's underage boyfriend into their establishments.

ADVERTISEMENT

The investigations were launched after the Cox Cable Channel 19's "In Business Las Vegas" reported Friday that Greek shipping heir Stavros Niarchos III accompanied his hotel heiress girlfriend into Tao at the Venetian and the Hard Rock Hotel's Body English on New Year's Eve, the Las Vegas Sun reported Sunday.

Hilton is 24. Niarchos has not yet reached 21, the legal age to go to Vegas clubs.

RELATED LINKS Paris Hilton Sex Tape Coverage RealityTVWorld: Nicole Richie RealityTVWorld: Paris Hilton RealityTVWorld: The Simple Life SirLinksALot: The Simple Life The Simple Life Message Boards More The Simple Life 4 News

While it was reported Hilton spent the bulk of her own party at Tao in the club's restaurant because of her boyfriend's age, revelers allege the pair sneaked into the club illegally after midnight, the Sun said.

They were also allegedly spotted at Body English later in the evening, but were not allowed into the Pure at Caesar's Palace, the newspaper said.

Tao refused comment on the probe, but Hard Rock President Kevin Kelley said his club was cooperating with authorities and conducting an internal investigation as well.

Hilton's reps did not return calls seeking comment.