Patrick Brown has been disqualified by the leadership election organizing committee of the federal Conservatives.
A statement from Brown's campaign calls the decision reprehensible.
It also says the committee's ``undemocratic behaviour'' breaks faith with hundreds of thousands of Canadians that embraced Patrick Brown's vision of a modern, inclusive Conservative party.
Committee chair, Ian Brodie, announced the surprising move late Tuesday night, saying the party had learned of ``serious allegations of wrongdoing'' by the Brown campaign.
Brodie says the allegations are related to the financing rules in the Canada Elections Act, but provided no further details.
The Brown campaign is accusing the party of basing its decision on ``anonymous allegations'' and not providing the full details or evidence.
It also accused the party of making this decision to favour Pierre Poilievre, the longtime Ottawa-area M-P considered a front-runner in the race -- and the main rival to Brown.
As of late Tuesday night, the Poilievre campaign had not commented on the news.
The Conservatives will announce the winner of the leadership race in Ottawa on September 10th.