The director of Canada's security services said that at least two high-ranking provincial politicians were believed to be under the control of foreign governments.
Richard Fadden said two provincial cabinet ministers "have developed quite an attachment to foreign countries".
He said several members of municipal governments in British Columbia were also under suspicion.
He did not name the politicians or countries suspected of being involved.
Mr Fadden, who heads of the Canadian Security Intelligence Service, was speaking to the CBC's The National programme.
He said the politicians involved had no idea they were being used, and that his agency was in discussions on how best to notify the provinces concerned.
"We're in fact a bit worried in a couple of provinces that we have an indication that there's some political figures who have developed quite an attachment to foreign countries," he told the CBC.
He said the individuals were being targeted early on in their careers, with a view to developing a relationship that could be exploited at a later date.
"The individual becomes in a position to make decisions that affect the country or the province or a municipality. All of a sudden, decisions aren't taken on the basis of the public good but on the basis of another country's preoccupations," he said.
Mr Fadden said at least five countries were trying to recruit future political prospects in universities, including China and countries in the Middle East.