The 39-year-old was summoned to a Barcelona police station where he was “taken into custody” and will now be questioned by a judge, said a spokesperson for Catalonia’s regional police force, the Mossos d’Esquadra.
Catalan police received a complaint on January 2nd from a woman who said Alves had touched her inappropriately, police said.
The alleged sexual assault took place at a popular Barcelona nightclub overnight December 30th-31st, according to Spanish media reports.
The player was accused of putting his hands down the woman’s pants, according to the reports.
Alves, 39, has confirmed he was at the night club at the time but has denied any wrongdoing, telling private Spanish television Antena 3 earlier this month that he has “never seen” the woman before.
“I was there, at that place, with more people having fun. Everybody knows I love to dance. Having a good time but without invading the space of others,” the former Barcelona and Juventus player added.
Alves, who now plays for Mexican side Pumas UNAM, was in Barcelona on holiday following his participation at the World Cup with Brazil in Qatar.
A Barcelona court said earlier this month it had opened a probe “into an alleged crime of sexual assault as a result of a complaint filed by a woman against a footballer”.