The Spanish National Police have arrested 21 men between the ages of 15 and 22 for their involvement in violent gangs.
They are alleged to have committed violent robberies, serious threats and bodily harm.
The majority of the victims have been minors who were threatened and in some cases attacked with bladed weapons in recreational areas according to the Superior Police Headquarters.
The Provincial Police Station of Valencia launched an operation last December to track down the youth groups that were involved in altercations in central areas of Valencia, most of which took place on weekends.
They are accused of disturbances to public order, damage to street amenities, violent robberies and injuries with bladed weapons.
The perpetrators are said to have acted in groups of 10 to 15 people, masked by balaclavas and neckerchiefs.
Targeted areas included leisure areas, discos, squares and subway stations as well as other areas where teenagers gather.
The assailants threatened victims with violence before robbing them of money and mobile phones. When victims showed the slightest refusal to hand over possessions they were faced with knives and blunt instruments.
Of those arrested three were of legal age and the rest minors.
The perpetrators were brought before the courts and the Juvenile Prosecutor’s office. The three adults have been placed in provisional prison, four minors have been interned in a Juvenile Center and the remainder are on probation.
The crimes committed by these groups continue under investigation and more arrests have not been ruled out.