Corinthians fans attacked Peruvian striker Paolo Guerrero after invading the team’s training centre in Sao Paulo in protest at the Brazilian team’s recent struggles, club president Mario Gobbi has said.

Gobbi said the protest turned violent and fans grabbed the striker by the neck. He said other club employees were also attacked during Saturday’s confrontation after about 100 fans broke in. Nobody was seriously injured.

The training centre, in Sao Paulo, will be used by the Iran national team during the World Cup in the summer. Corinthians’ stadium, the Itaquerao, will host the tournament’s opener between Brazil and Croatia.

Gobbi told Radio Jovem Pan that Guerrero, who scored the winner against Chelsea in the Club World Cup final in 2012, was attacked.

“They tried to strangle the player who scored the most important goal in team history. We didn’t deserve this,” he said.

He said the club had already contacted police and would help authorities arrest those responsible for the attack, with security camera footage being handed over to investigators.

“This is a case for the police to handle,” he added. “Our employees don’t feel safe any more.”

The fans cut through a wire mesh fence to try to reach Corinthians players. Local media reported that they also targeted striker Emerson Sheik and former AC Milan forward Alexandre Pato, the club’s most expensive signing last year, along with coach Mano Menezes.

As the World Cup kick off is approaching , much concern and alarm has been raised by the various events surrounding the tournaments from strikes, riots against the World Cup and now this security breach in a training camp. The authorities in Brazil has promised tight security for all the visitors and teams.