PAMPLONA, Spain, July 8 (Reuters) - Thousands of San Fermin festival-goers at Pamplona's famed bull run have protested against a rising number of sexual attacks that have marred the image of the week-long event following the reported assault on a young woman.

The protest came after a 19-year-old woman was reportedly attacked in the early hours of Thursday morning, the second day of the festival. Five men have been arrested in connection with the assault.

Holding banners reading "No means no" and "No to violence against women" while wearing the celebration's traditional red bandannas and white t-shirts, a crowd gathered outside the town hall on Thursday evening holding their hands in a "stop" gesture and chanting slogans.

The festival has become infamous for its alcohol-fuelled street parties and increasingly common reports of sexual assaults, including men groping women's breasts at the opening party known as the "Chupinazo". (Reporting by Susana Vera; Writing by Catherine Bennett; Editing by Paul Day/Jeremy Gaunt)

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