A group of 10 people on Saturday vandalized the house of the brother of the main suspect in a shooting. The killing took place in a cemetery in Figueres on Friday, and saw 30-year-old Santiago Gabarre, from Perpignan, France, shot dead.
The alleged killer and the victim are from different Gypsy clans, which are involved in an ongoing war.
The police said they were working on the assumption that the culprits behind the damage to the house belong to the family of the dead man.
The shooting occurred on All Souls Day at the Figueres cemetery in Alt Empordà, Girona. The incident took place after two men were ejected from the graveyard by clan leaders after an argument broke out. The altercation continued outside the gates, and culminated in the killing.
Police deployed a large force on Friday to try to avoid reprisals.