The Conservative Party of Canada has removed 1,351 names from its membership list after discovering they were purchased anonymously and inappropriately.
The announcement from the party comes a day after reality TV star and Tory leadership candidate Kevin O'Leary alleged "widespread vote rigging" in the race to replace Stephen Harper as the next permanent leader of the Conservative Party.
"Upon an expedited review, we found 1,351 memberships purchased through two IP addresses which were not purchased by those members. Those purchases were made anonymously through the Conservative Party of Canada website," communications director Cory Hann said in an email to CBC News.
"The memberships purchased in contradiction to the published rules have been removed from our membership list, and are no longer eligible to vote."
On Saturday, O'Leary and fellow leadership candidate Maxine Bernier addressed the fraudulent memberships.
Bernier refused to apologize for calling O'Leary a "loser," after The Canadian press quoted sources saying O'Leary had accused Bernier's team of having a role in the fraud.
"No, because what he was saying when he was speaking to the media was that it was our team that did that. But I can assure you it was not our people," he said.
Later Saturday, O'Leary told CBC News that he hadn't made any allegations against Bernier.
"Who has done this nefarious activity is unknown," he said. "I have no idea who's done this and I'm sure he joins me in wanting this to be fully above board."
O'Leary also emphasized he wanted to see a full audit of all memberships before March 28, the last day new members are allowed to join and cast a vote in the leadership race.
On Thursday evening, O'Leary issued a statement alleging that "backroom organizers" were using untraceable prepaid credit cards to sign up new members, in some cases without their knowledge, and called for the party to look into the matter.
After an investigation, the party discovered that some of those allegations appeared to be true.
"Over the course of the last six months, the Conservative Party of Canada has received 1,233 prepaid credit card transactions through our website," Hann said.
"We have examined each of those transactions and roughly half of those have been traced to the mentioned IP addresses purchasing memberships," he added.
Hann said members of the party can be reassured the contest is — and will remain — fair, and that all the rules for purchasing memberships are being followed.
On Friday, interim Conservative Leader Rona Ambrose had stressed the party has a sound voting process that does not easily lend itself to fraud. All voters submitting their ballots by mail are required to send a photocopy of their photo ID, she noted.
"Look, nobody can vote unless they've paid for their own membership," she said in an interview with CBC Radio's The House. "There's a whole list of requirements … it's very easy to spot these kinds of anomalies.
"Right now the party is looking into it."