Spanish police detained Brazil defender Dani Alves on Friday after questioning him in a police station in Barcelona over a sexual assault allegation, a spokesperson for the local Mossos d'Esquadra force told Reuters.

Alves, who has denied the allegation, will appear before a judge later on Friday, the spokesperson added.

It was unclear whether Alves, 39, would remain in police custody after the hearing.

The alleged victim told police that the Brazil and former Barcelona soccer star touched her under her underwear without her consent at a Barcelona nightclub on the night of Dec. 30.

Accompanied by her friends, the woman reported the incident to the nightclub's security staff, who then alerted police.

Officers arrived at the scene and took a statement from the woman. She filed an official complaint for sexual assault on Jan. 2.

Alves told Antena 3 in an interview earlier this month that he was at the club with other people but he denied any such behaviour.

"I was dancing and having a good time without invading anyone's space," he said. "I don't know who this lady is...How could I do that to a woman? No."

Alves, who played for Barcelona from 2008-2016 and briefly returned to the Spanish team for the 2021-22 season, currently plays for Mexican club Pumas UNAM.

He has played for the Brazil national team since 2006, making 126 appearances and scoring eight goals.