ITALY’S maverick anti-Establishment and Eurosceptic Five Star Movement (M5S) achieved a huge breakthrough yesterday, winning mayoral elections in Rome and Turin.

The victories are a massive slap in the face to Prime Minister Matteo Renzi’s Democratic Party (PD), which grew out of the wreckage of the old Italian Communist Party but has since adopted the European Union’s austerity agenda.

M5S candidate Virginia Raggi, a popular 37-year-old lawyer, took 67 per cent of the vote in the Rome mayoral run-off, against PD hopeful Roberto Giachetti, making history as the city’s youngest and first woman mayor.

“A new era is beginning with us. We’ll work to bring back legality and transparency to the city’s institutions,” she said.

She ran on a platform focused on fighting corruption and cronyism.

An even bigger embarrassment for the prime minister is his party’s shocking defeat in his stronghold Turin, where incumbent Piero Fassino was swept away by M5S candidate Chiara Appendino.

Ms Appendino, who is 32, took 55 per cent of the vote.

Mr Renzi’s main consolation victories were in the financial capital Milan, where his candidate Giuseppe Sala won with 51.7 per cent, and traditional Communist stronghold Bologna.

Around 8.6 million people — one-fifth of the total electorate — were eligible to vote in the second round of Italy’s mayoral races, held in 126 towns where no candidate received over 50 per cent of the first round on June 5.

M5S, led by comedian Beppe Grillo, has shown stellar results during the mayoral elections and is currently Italy’s leading opposition party.

The movement has set itself more against corruption than austerity, with a referendum on eurozone membership and environmentalism key policy platforms, and has aligned itself in the EU Parliament with Britain’s Ukip and other right-wing populist forces.

The PD has been weakened by defections and scandals in Rome, which tainted local Democrats as well as conservative politicians, while many Democrats chafe at Mr Renzi’s brash management style bordering on arrogance.