A savage attack on a Dutch couple who were holidaying in Rome has revived the debate in Italy over crime and immigration.

After the assault on Friday last week – in which the woman was raped in front of her husband by two Romanian men and had most of her teeth knocked out – left-wing politicians said it showed that the crackdown on street crime and illegal immigration by the centre-Right since it returned to power in May was “only words”.

However Gianni Alemanno, the Mayor of Rome, said that the attack was an isolated case. He said that the couple from Eindhoven, who are in their fifties, had acted unwisely in not staying at an authorised campsite while on a cycling holiday. Instead, they pitched their tent beside an abandoned farmhouse used by down and outs at a “godforsaken” spot in the suburb of Ponte Galeria, the mayor said.

Two Romanian shepherds identified by the couple as their assailants have been arrested and charged with sexual violence, kidnapping and grievously bodily harm. Police said that one of the men had been ordered to leave Italy two years ago for illegal entry, but had failed to do so.

Police said that after assuring the Dutch couple – Roman Catholic pilgrims and had just visited St Peter’s – that the area was safe, the shepherds had returned at night, stolen €1,500 (£1,200) and then beaten the couple “to a bloody pulp” with clubs. The couple are being treated for shock and multiple fractures at the San Camillo hospital, Rome. Doctors said that the woman was almost unrecognisable.

Italian media compared the attack with the murder in October last year of Giovanna Reggiani, the wife of a naval officer, as she was returning to her flat from the suburban railway station of Tor di Quinto along a path close to an immigrant shanty town.

The trial of Nicolae Mailat, the Romanian immigrant accused of the killing, opens next month. The murder contributed to a wave of public fear over street crime and immigration that brought the Right to power both nationally and in Rome this spring.

However, Maria Pia Garavaglia, the former centre-left deputy mayor of Rome, said that while the Right had blamed street crime on the “lax” Italian Left during the election campaign, the latest attack showed that the Right had no magic wand either. She said its deployment of troops on the streets of Italian cities alongside police was a propaganda exercise.

Mr Alemanno, who is on holiday at Cortina d’Ampezzo, said that the centre-right crackdown had only just begun. He said: “We are bringing people greater security depite being accused by the Left at every step of intolerance and discrimination.” He added that the Left’s criticisms were absurd.

“They were asleep when they ruled Rome for 15 years and now they complain because we have taken decisive action in just four months.” He said troops would remain alongside police on street patrols for at least a year.