Police release photos in search for witness to New Year's Day sexual assault

Police are searching for a man who may have witnessed an alleged sexual assault in Melbourne earlier this year.

The alleged assault took place at Billboard Saturdays nightclub on Russell Street in Melbourne East on New Year's Day.

Police believe the male witness helped the female victim when she collapsed at the club and have released images of the man in a bid to identify him.

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In the photos he appears to be a tall Caucasian male with no facial hair and short hair parted on one side.

He's wearing a button-up shirt with long sleeves, pants and sneakers in the photos.

Anyone with information about the witness's identity or the sexual assault can contact Crime Stoppers on 1800 333 000 or anonymously online.

A different man has already been arrested in relation to the alleged sexual assault at the nightclub and another at nearby Corrs Lane.

Police confronted the 22-year-old French national at Sydney International Airport on January 4.

He was extradited to Melbourne the following night and charged with six offences, including two counts of rape and two counts of sexual assault.

He will next appear before Melbourne Magistrates' Court on May 22.

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