La Liga's governing body has called for Espanyol fans to be punished for alleged homophobic and racist abuse during last Saturday's 2-0 loss to city rivals Barcelona.
The National Professional Football League (LFP) sent officials to monitor crowd behaviour at the fixture, from which away fans have been banned due to trouble at previous games, at Cornella-El Prat.
And it has now issued a complaint to the Spanish government's anti-violence commission.
According to the LFP, home fans directed monkey noises towards Barca's Neymar and Dani Alves, chanted a homophobic song in the direction of Gerard Pique and insulted Jordi Alba after he was sent off early in the second half.
An LFP statement read: "The offending insults are described below, they were chanted exclusively by supporters of Real Club Deportivo Espanyol, SAD, recognisable by their different flags, scarves, shirts and banners, located in sectors 108, 109, 110 and 111 in the Gol Nord part of the stadium, specifically by the group known as 'LA CURVA RCDE'.
"The chants and insults were shouted in a co-ordinated and repeated manner, by groups of between 300 and 600 supporters, situated on both sides of the central area of the stand behind the goal, and, owing to a protest organised by the aforementioned supporters group 'La Curva' during the first half, the fans in sections in 109 and 110 fought each other at this moment, close to the zones 108, 111 and the other surrounding free areas, from where they shouted the aforementioned shouts, leaving sectors 109 and 100 practically empty during the first half."