Spain's national police have arrested four people responsible for a hate campaign against Real Madrid forward Vinícius Júnior.

The investigation began following three complaints filed by LaLiga ahead of Madrid's 1-1 league draw at Atlético Madrid on Sept. 29.

Police confirmed to ESPN that those arrested "incited fans through social media to go to the [Metropolitano] stadium to utter insults with racist connotations" aimed at Vinícius.

Some fans had claimed on social media that they would attend the game at the Metropolitano wearing masks, enabling them to racially abuse the Brazil international without being identified.

Vinicíus, 24, has frequently been targeted with racist abuse from opposition fans since arriving in Spain in 2018, including at the Madrid derby.

Last year, four Atletico fans were charged after an effigy of Vinicíus was hung from a bridge.

In June, three Valencia fans were jailed for eight months for racially abusing Vinícius during a LaLiga game in May 2023, in the first verdict of its kind in Spain.

Last month, a Spanish court handed a 12-month suspended sentence to a Mallorca supporter that used racists insults against Vinícius and Villarreal's Samuel Chukwueze in February 2023.