Fans of Valencia and Barcelona clashed outside Mestalla ahead of the LaLiga Santander meeting between the two sides on Saturday.
Supporters of both teams hurled chairs and flares at each other near the entrance of Valencia's stadium.
Three hours before the start of Valencia-Barça which scheduled for 16 pm local time in Mestalla, the vicinity of the stadium have been the scene of a brawl between members of the Yomus and Boixos Nois, groups of radical fans of both teams.
In the Square of Fans, the two sides have met with about fifty members in each and have flown chairs from near bars. The police were forced to multiply and intervened. The fight has stopped and the Boixos have moved away to another place in the city.
With several National Police vans next to the stadium, the situation has been controlled in the aforementioned Square, waiting for the 50,000 fans who will fill Mestalla for a game that has become high-risk in the streets.