Police in northern Brazil say one man has been arrested after a referee who fatally stabbed a player during a match was decapitated by spectators who stormed the field.Local reports said the incident, which took place on 30 June in the remote Brazilian town of Pio XII, escalated when the player, 30-year-old Josenir dos Santos, became involved in an argument with the referee, Octavio da Silva.As the confrontation became physical and Dos Santos refused to leave the field, Da Silva allegedly produced a knife and stabbed the player, who died while being taken to hospital.Reports said that outraged spectators responded by running on to the field and stoning Da Silva, before severing his head and sticking it on a stake in the middle of the field.Police at the regional headquarters of Santa Ines said a 27-year-old man was arrested on 2 July, with the investigation continuing.Police spokesman Valter Costa was quoted as saying: "We will identify and hold accountable all those involved in this incident. One crime will never justify another. Actions like this do not correspond with state law."Brazil faces mounting pressure to show it is a safe place for tourists before 12 cities host the 2014 World Cup and Rio de Janeiro the Olympics in 2016.The Confederations Cup in June was marked by violence as anti-government protestors angered by the amount of money being spent on the events clashed with police.