The brother of a convicted mobster has broken a reporter's nose during an interview on local municipal elections in Ostia, a neighbourhood in Rome.

Roberto Spada headbutted journalist Daniele Piervincenzi and subsequently attacked him and filmmaker Edoardo Anselmi, both from Rai2's programme Nemo Nessuno Escluso, with a baton stick.

The assault was caught on camera and the video was widely shared on social media on Wednesday, 8 November, prompting calls for an investigation into the incident.

The video shows Piervincenzi telling Spada, outside the gym he owns, "I am here because newspapers, and you read them, said that the clan Spada and Roberto Spada support CasaPound and this support has made CasaPound win 18% in Nuova Ostia".

CasaPound is a pro-Fascism and anti-immigration political party. The group scored 9% in Ostia's municipal elections earlier in November.

Spada replies: "I don't know, I don't read newspapers, you know about it".

As Piervincenzi asks more questions, Spada headbutts him and then chases him and his colleague with a baton.

"You have been here for two hours," Spada says. The reporter can be heard saying: "You broke my nose, I am leaving if you want me to, but say it calmly."

The end of the footage shows Piervincenzi walking away, his face covered in blood.

The Spada clan, of Sinti origins, has been involved in several probes on usury, extortion, drug trafficking and public domain concessions in Rome, according to Il Messaggero.

Spada's brother, Carmine, was sentenced to 10 years in prison for extortion, a charge aggravated by the so-called "mafia method" crime .

Spada justified his action in a post - later deleted - on his Facebook page, accusing the two journalists of "forcing their way into a members-only club, disturbing a session and frightening my son," news agency Ansa reported.

"What would you have done?" he said. "In the last 10 days at least 30 journalists have come to break our balls, patience has a limit".

Piervincenzi told Ansa that Spada should apologise for his action. He also denied that he and his colleague frightened Spada's son.

"It was an unexpected thing, I was doing an interview. We were trying to understand the reasons for the [Spada clan's] endorsement for CasaPound", he said.

"I have a compound fracture of the nasal septum," said Piervincenzi. "But we're still on our feet. I don't think I scared anyone, I'm the scared one.

"If he apologises I'm ready to forgive him, but he should apologise to Ostia, where the high crime rate and the clans have spoiled the social fabric of a beautiful place."

The mayor of Rome, Viriginia Raggi, condemned the attack. "Spada clan violence unacceptable. Solidarity to journalist and filmmaker attacked in Ostia. We'll stop crime and extremism in Rome," she said on Twitter.

The deputy head of CasaPound, Simone di Stefano, also condemned Spada's attack and said they had nothing to do with the clan.

"Roberto Spada is not a member of CasaPound. We share nothing with him, apart from attendance at a kid's party in a piazza 18 months ago," Di Stefano said, according to Ansa.

He later wrote on Twitter: "As a minimum of intellectual honesty does not exist, I am only going to say 'no comment' with regards to the Roberto Spada event. And now, you can write whatever you make up, as usual."

Interior minister Marco Minniti said the police were working on the case. Ansa quoted judicial sources as saying that a criminal probe had been opened and that Spada is suspected of bodily harm, a charge that can change to grievous bodily harm if the reporter's condition worsens.