The Canada Revenue Agency says it has conducted 15 raids in Quebec and Ontario as it investigates an alleged multi-million-dollar case of tax evasion.

The agency says that it conducted the raids in Ottawa, Montreal and the Greater Toronto Area, as well as Gatineau, Que., Laval, Que., London, Ont., and Windsor, Ont. on Wednesday.

All of the raids were part of the same investigation, which CRA says involves $8.3 million worth of evaded taxes. According to the CRA, its personnel and RCMP officers searched the 15 locations for evidence that could further the investigation.

CRA alleges that criminal offences and income tax law violations were committed.

The maximum penalty for income tax evasion is five years in prison and a fine equaling double the amount of tax evaded. If prosecuted as criminal fraud, a conviction for tax evasion can lead to prison sentences of up to 14 years.

The federal government says it has given the CRA more than $1 billion to catch tax evaders, although critics have argued that the country lags behind Australia and other jurisdictions’ similar efforts.

Parliamentary Budget Officer Yves Giroux has attempted to get a clearer picture of tax evasion in Canada. He said in April that he has not been provided with all the information he would need to measure the gap between the amount of taxes paid in Canada and the amount that should be collected.

Not having access to that data makes it difficult to understand the full scale of the problem posed by tax evaders, he said.

Giroux is expected to release a study on corporate tax evasion this summer, although he has warned that it will not explore the issue in full.

With files from The Canadian Press