Ontario Premier Dalton McGuinty says he hasn't seen any evidence suggesting the Mafia's grip on Ontario's politicians and economy is as strong as alleged in Quebec, adding that if there were concerns, police would have told him.

The premier said Tuesday he has "no reason to believe" that officers would want to keep such allegations quiet or confidential if they are, in fact, grounded in reality.

"I would think they would have approached us in a constructive way some time ago," he said.

McGuinty was responding to a joint investigation by the Toronto Star newspaper and CBC's French-language investigative program Enquête, which turned up information that what’s thought to be the mightiest branch of the mob, the Calabrian Mafia or 'Ndrangheta, has extensively infiltrated his province's business and political spheres.

Valentina Tenti, an expert on the Mafia, says investigators in Italy have found the Calabrian branch of the mob has a strong presence in the Greater Toronto Area and Thunder Bay, Ont. (CBC)

"We went to Italy to investigate the importance of the Italian Mafia in the world and especially Montreal, and anti-Mafia investigators there told us, 'Forget Montreal. It's about Toronto now, with the most powerful Mafia in the world, the Calabrian Mafia,'" Enquête host Alain Gravel said.

The program spoke to former RCMP chief superintendent Ben Soave, who headed up the RCMP's anti-Mafia efforts in Ontario until 2004.

Soave said the Ontario economy is probably more infiltrated by the mob than Quebec's, and that there's just as much, if not more, corruption of politicians.

"They're probably more active than in Quebec.… from political figures to law enforcement to people in the criminal justice system, to the manufacturing industries, they've done that," he said.

"They have the same problem, the same corruption. They have the same organized crime groups operating here. Devastating as they are in Quebec, but they're much lower profile."

Gravel said sources told him the Ontario-based Mafia gets less attention because "in Quebec, you get the bodies. Here, we get the money."

Or as Mafia authority and writer Antonio Nicaso said, "If they're not shooting on the street, they don't create a social alarm, and people don't scream and people won't call their MPs saying 'Oh, we have a problem.'"

Rizzuto power war

The Montreal area has seen a spate of firebombings and killings in recent months that some crime experts are blaming on a power war involving the Rizzuto crime family, which once dominated the city's Mafia. Vito Rizzuto, the reputed kingpin of the Montreal mob, has been in a U.S. prison since 2007 for his role in three 1981 murders in New York state but is to be released next month.

The Rizzutos are from the Sicilian branch of the Italian Mafia, known as the Cosa Nostra. With Vito Rizzuto out of the picture, one theory is that the Ontario-based Calabrians are trying to make a comeback in Montreal after losing control of the city about 30 years ago.

McGuinty said Tuesday that he certainly wants to hear any allegations from law enforcement about Calabrian influence in Ontario, but that they should go through the proper channels.

"If there are serious and warranted allegations they need to be made in a substantive way, not through the media," he said at an agricultural fair he was touring in Ayr, Ont.

"I would expect that people in positions among our police services would be drawing this to our attention at the earliest possible opportunity."

Talk of 'Ndrangheta influence in the province was also highlighted in testimony Tuesday at Quebec's public inquiry into corruption in the construction industry. Witness Valentina Tenti, a PhD criminologist and expert on the Italian Mafia, said Italian Mafia investigators have found the 'Ndrangheta to be particularly strong in the Greater Toronto Area and Thunder Bay, Ont.

With files from The Canadian Press