The 34-year-old supporter was attacked by 15 fans armed with metal bars at a bus stop following a league game between Santos and Sao Paulo.

Another fan, aged just 15, was in a serious condition after being attacked at a metro station, according to local media.

The victim, named by Globo television as Marcio Barreto de Toledo, had been with two other Santos fans when the attack took place. They managed to escape.

He was married and had a five-month-old baby.

Mr Toledo died in hospital early on Monday morning. No arrests have been made in connection with his killing.

Sao Paolo will host the opening match of the World Cup

Brazil will host the World Cup starting on June 12 and Sao Paulo will host the opening match of the tournament. The city saw more protests about the country's hosting of the event on Monday.

The country has been beset by repeated incidents of violence at matches in recent months.

Fans of Corinthians burst into the club's training centre last month and tried to strangle Peruvian striker Paolo Guerrero and threatened to break the legs of former striker Alexandre Pato, who subsequently left the club.

In December, supporters of Vasco de Gama and Atletico Paranaense clashed, with one fan having to be airlifted to hospital from the side of the pitch.

Last week, authorities and Fifa revealed 170,000 security personnel, including 20,000 private professionals, will be deployed at the 12 World Cup venues in Brazil during the tournament.

President Dilma Rousseff said troops would also be mobilised "if necessary" to ensure fan security.