The Spanish league says it will send a report denouncing racist and abusive language by fans during Espanyol's home match against Barcelona last Saturday to the Spanish government's anti-violence committee for sports.
The league said in a statement that it will condemn racist slurs directed toward Barcelona's Brazilian striker Neymar and abusive chants against the club.
It said they broke the Spanish football federation's disciplinary code, which prohibits chants that "incite violence, racism, xenophobia and intolerance in sports."
The teams played again in the Copa del Rey on Wednesday, when tempers flared and two Espanyol players were sent off in a 4-1 Barca win.
Espanyol players later said Barcelona players provoked a heated exchange after the match.
The statement said: "Under the rules of the Royal Spanish Football Federation, the Professional Football League's Anti-violence Commission will send a letter denouncing the chanting of songs that incite violence, racism, xenophobia and intolerance in sport, with these actions are contrary to the legal system foreseen in the RFEF Disciplinary Code. This same letter of complaint will be transferred to the Competition Committee.
"Throughout this section and subject to concern a public and notorious fact, are listed the following behaviors that form the subject of this complaint and related with the match between RCD Espanyol, SAD and FC Barcelona, on Jan. 2, 2016, of Liga BBVA matchday 18.
"1. In the 14th minute, and when the referee awarded an offside to the player Neymar Jr, number 11, the cry "UHHHH" was heard, without being able to locate the area of origin, since numerous whistles from the stands were also heard.
"2. In the 22nd minute, and during an argument between the players of both teams while the game was stopped, from the Cornella Goal Zone, sections 109 and 110, where home fans from the group known or called "La Curva" are located, the chant "Puta Barça, puta Barça, eh" was initiated by a fan carrying a speaker, which was seconded in a coordinated way for about 250 people in the same area and by the same group during 10 seconds. This chant was not supported for the rest of the fans.
"3. In the 28th minute, and during the course of it, from Cornella Goal zone, sections 109 and 110, where home fans from the group known or called "La Curva" are located, the chant "Luis Enrique, tu padre es Amunike!", referring to the visiting coach, was initiated by a fan carrying a speaker, which was seconded in a coordinated way for about 250 people in the same area and by the same group during 10 seconds. This chant was not supported for the rest of the fans."
The city rivals will play the return leg of their cup tie next week at Espanyol.