Two and a half years after the landmark Panama Papers leak of offshore financial information, the Canada Revenue Agency has yet to charge or convict anyone with offshore tax evasion.

"To date, no Canadian taxpayer or company has been charged with an offence as a result of information received from the Panama or Paradise Paper affairs," said Dany Morin, spokesman for the department.

While the CRA currently has 50 "mature" investigations into offshore tax evasion, it appears that few of them are related to the Panama Papers, a massive leak of confidential offshore financial information that rocked the world and led to the resignations of top government officials in a number of countries.

"In relation to the Panama and Paradise Papers specifically, several criminal investigations are ongoing," wrote Morin.

"As with any criminal investigation undertaken by law enforcement bodies, including the CRA, these can be complex and require months or years to complete."

Morin refused to state exactly how many ongoing investigations are related to the Panama or Paradise papers, saying it would jeopardize the agency's investigative work.

The agency's review of the Panama Papers has identified 3,330 offshore entities with "2,670 possible beneficial owners that have some link to Canada."

Meanwhile, "the agency is currently auditing over 1,100 taxpayers with offshore links."

NDP MP Pierre-Luc Dusseault said Canada is taking longer than other countries to act on the information contained in the Panama Papers.

"In different countries, those revenue agencies take this very seriously and they go fast," he said. "They don't wait three years to get things done."

"Here in Canada, it is unfortunate that it takes so long," he said, suggesting that the Liberal government is being influenced by wealthy donors.

Revenue Minister Diane Lebouthillier and CRA officials came in for an opposition grilling over their handling of offshore tax evasion Tuesday, when they appeared before the House of Commons Finance Committee to answer questions about a critical report by Canada's auditor general which found that the agency didn't apply tax rules consistently.

Dusseault also questioned a donation that Lebouthillier's riding association received from former Liberal senator Leo Kolber.

NDP MP Pierre-Luc Dusseault says Canada is too slow to investigate offshore tax evasion by Canadians. (Adrian Wyld/The Canadian Press)

Elections Canada records show that Kolber and his wife, Ronith Hirsch-Kolber, each contributed $225 to LeBouthillier's Gaspésie-Les Iles de la Madeleine riding association on Dec. 20, 2016.

They were the only contributors to the revenue minister's riding association who do not live in the riding.

Kolber is a wealthy Montrealer with close ties to the Bronfman family who has donated generously to the Liberal Party of Canada over the years. He was thrust into the headlines in November 2017 after the Kolber Trust he set up in the Cayman Islands in 1991 was included in the Paradise Papers leak.

Reached at her Montreal home, Hirsch-Kolber said her husband was too ill to do an interview. She said she didn't know anything about the donation that is listed in her name.

Dusseault questioned why Lebouthillier accepted the contribution from Kolber.

"Why is she accepting dollars, even one dollar, from a very well-known former Liberal senator who has his two hands right in the Paradise Papers?" he said.

"When she received the donation, she just should have said, 'No thank you' and (given) back the money."

Lebouthillier defended accepting the contributions from the Kolbers.

"You will understand that I will not lose my reputation for $225," she said on her way out of the meeting.

Lebouthillier said she held two fundraisers in the Gaspé and neither cost $225 a head to attend.

A few hours later, Dusseault raised the same question during question period, calling the Liberal government's vows to fight tax evasion "a smoke screen."

"The revenue minister herself accepted a donation on the part of an influential Liberal cited in the Paradise Papers," he told the House. "Now we understand her inaction better. As they say, we don't bite the hand that feeds us."

Lebouthillier shot back.

"What my colleague is trying to do is to indirectly associate me with the Paradise Papers. If he wants to play that game, I invite him to look in his own backyard," she said.

"Mr. (Jagmeet) Singh and (Tom) Mulcair, as well as the MPs for Timmins-James Bay (Charlie Angus) and Skeena -Bulkley Valley (Nathan Cullen), have all accepted contributions from individuals named in information leaks."

Emilie Gagnon, Lebouthillier's press secretary, said those donations to candidates running in last year's NDP leadership campaign, totalling $1,210 between 2012 and 2017, were made by Robin Sears.

Sears also appears in the Paradise Papers as a shareholder in Recipco Holdings incorporated in Bermuda.

Contacted by CBC News, Sears said he holds a small investment in the company, set up by a friend more than 20 years ago. He said he has given money to lots of different candidates, including Liberal cabinet minister Carolyn Bennett and Ontario provincial cabinet minister Caroline Mulroney.

"If this is the best they can do, there's not much there, or they should hire new researchers," he said. "I don't think there is much of a smoking gun in this case."

Elizabeth Thompson can be reached at elizabeth.thompson@cbc.ca