Elections Canada is looking into 800 complaints from voters about robocalls and live calls made in 200 ridings during the last federal election, the agency's head said Thursday.

Chief electoral officer Marc Mayrand wouldn't comment specifically on the ongoing investigation in the Ontario riding of Guelph, or confirm how many official investigations are underway, but he did tell MPs that 250 case files have been opened at the chief election commissioner's office.

He cautioned that some complaints can be combined into a single file or investigation.

Mayrand, appearing at the Commons' procedure and House affairs committee on the subject of "allegations of wrongdoing" during last May's general election, said 70 complaints were received immediately after the election related to improper communication. People said they received live and automated calls purporting to be from Elections Canada that told them their polling station had been changed.

Elections Canada does not phone voters to inform them of polling station changes. Mayrand said some cases involved a person falsely claiming to be calling from a party or campaign. People have also complained about calls that were harassing and rude in nature and were received at inconvenient times.

"Any action taken to deliberately misdirect electors and interfere with their right to vote under the Constitution and the Elections Act is a serious offence," he said in his opening statement. "It not only denies the fundamental rights of affected electors, but it also diminishes our democratic institution and the rights of all Canadians."

He later called the attempts to misdirect voters "absolutely outrageous" and said whoever is responsible should face serious sanctions. He also said the Elections Act should be reviewed to ensure that its penalties are strong enough.

"It's totally unacceptable in a modern democracy," he said of the attempts to misdirect voters.

Leaks within Elections Canada

Conservative MP Dean Del Mastro, parliamentary secretary to the prime minister, asked Mayrand whether he could confirm that there have been no information leaks coming from his organization.

"There are a number of folks in the media that have, in fact, came forward and indicated to me that they feel Elections Canada has been the source of some of these things," he said. It was a theme Del Mastro returned to during a scrum later in the day.

Mayrand, however, dismissed the suggestion. "There is no source leaking from Elections Canada, if that is the allegation. I can attest to that," he said.

When the robocalls story broke in the media in February about the Elections Canada investigation in Guelph, Mayrand said the agency subsequently received 40,000 "contacts." Those involved people expressing their concerns and didn't all involve specific cases.

The agency has 800 specific allegations of fraudulent or improper calls, he said, that are being reviewed to see if they warrant further investigation.

The commissioner's office determines whether there is sufficient evidence and if a complaint is considered too vague, it is dismissed.

"We have added sufficient resources to deal with the inflow of communication and to contact electors who have specific, factual allegations," he said.

Mayrand said people should not draw conclusions before the election commissioner has finished his investigation.

He intends to complete a report within a year about how electors are communicated to in the context of evolving technologies.

"I think we can say that Canadians are proud of their electoral system and that they should be," Mayrand said, but he added that voters' trust and confidence has been shaken by the robocall story.

He said Elections Canada diligently looks into complaints about irregularities and improper conduct.

Attention on federal budget

Mayrand's appearance at the committee took place on a day when Parliament Hill's attention will be turned to the federal budget, to be tabled by Finance Minister Jim Flaherty at 4 p.m. ET.

Mayrand said he would be willing to come before the committee when he released a statement two weeks ago. The government chose Thursday as the date for his appearance.

The chair of the committee, Conservative MP Joe Preston, said on Wednesday that the committee didn't have any other business scheduled for the day and it was the earliest Mayrand could appear.

Elections Canada previously said it is investigating the source of fraudulent phone calls, claiming to be on behalf of the electoral agency, that directed voters in the Ontario riding of Guelph to the wrong polling station. Under the Canada Elections Act it is illegal to impersonate an Elections Canada official and to misdirect voters.

Since news of that investigation was reported in the media, voters in ridings across the country have come forward with stories of similar calls, both automated and live.

Elections Canada has revealed few details about the probe because it is ongoing but some details have been revealed because of court documents. Mayrand said a final report will be made public.

Calls traced to firm hired by Tories

What is known about the Elections Canada probe is that it traced the fraudulent robocalls in Guelph to an automated calling service based in Edmonton. The company, RackNine Inc., is co-operating with the investigation to determine the identity of the client who uploaded the robocall to the service.

RackNine was hired by the Conservative national campaign and several local campaigns.

Mayrand warned in his March 15 statement that conclusions should not be drawn prematurely. But opposition MPs had already accused the Conservatives of being behind a widespread campaign of voter suppression.

There is no evidence that the Conservative campaign was behind the mysterious robocalls in Guelph, or anywhere else.

Read Kady O'Malley's liveblog of the committee testimony:

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