Lindsay Lohan's behind-the-scenes boozing has been made public by bosses of a Las Vegas nightclub who claim to have seen the actress downing vodka.

The Mean Girls star - who is newly-single after splitting from girlfriend Samantha Ronson - has been outed by management at Prive nightclub in the Planet Hollywood Resort & Casino, for drinking alcohol when she claims to be teetotal after several stints in rehab.

According to TMZ, the nightclub released a statement saying:  "Mel [B] was drinking Merlot and Lindsay asked for a Vodka drink mixed with soda water and a splash of cranberry."

Lindsay lashed out at a reporter who quizzed her about her relationship with alcohol only last week, responding with: "I don't drink...a**hole."

The actress attended rehab and Alcoholics Anonymous meetings for alcohol and substance abuse in 2007.

At the time Lindsay released a statement saying: "I have made a proactive decision to take care of my personal health.

"I appreciate your well wishes and ask that you please respect my privacy at this time."

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