Rishi Sunak has pulled support from candidates Craig Williams and Laura Saunders over the General Election betting row.
The Prime Minister acted after coming under mounting pressure within the party to take a tougher stance on the alleged use of inside information to bet on the timing of the July 4 poll.
In a sign of the wider scope of the Gambling Commission’s investigation, the watchdog passed information to the Metropolitan Police alleging that five more officers had placed bets related to the timing of the poll.
Labour also suspended parliamentary candidate Kevin Craig, who is being investigated by the Gambling Commission after he placed a bet that he would lose the contest for the Central Suffolk and North Ipswich constituency to the Conservatives.
The row has overshadowed the Tory election campaign in recent days as Mr Sunak battles to close his party’s 21-point average poll deficit to Labour.
Because nominations have closed, Mr Williams – who is standing in Montgomeryshire and Glyndwr – and Ms Saunders will both still be on the ballot paper.
But a Conservative Party spokesman said: “As a result of ongoing internal inquiries, we have concluded that we can no longer support Craig Williams or Laura Saunders as parliamentary candidates at the forthcoming General Election.
“We have checked with the Gambling Commission that this decision does not compromise the investigation that they are conducting, which is rightly independent and ongoing.”
Mr Williams said he “committed an error of judgment, not an offence”.
In a video statement he said he was “fully co-operating with the routine inquiries for the Gambling Commission and I intend to clear my name”.
Meanwhile, Scotland Yard said five more officers – in addition to a member of Mr Sunak’s protection team who was arrested earlier this month on suspicion of misconduct in a public office – were alleged to have placed bets.
The officers are based on the Royalty and Specialist Command, the Parliamentary and Diplomatic Protection Command and the Central West Basic Command Unit, but none of them work in a close protection role.
A Met Police spokesman said: “It is still the case that only one officer is under criminal investigation.
“We have, however, been passed information from the Gambling Commission alleging that five further officers have placed bets related to the timing of the election.
“The Gambling Commission continues to investigate these matters. The officers have not been arrested but the Met’s Directorate of Professional Standards has been informed.”
Decisions on whether the five officers will be subject to any restrictions will be taken in due course, the Met said.
Ms Saunders’s husband Tony Lee, the party’s director of campaigning, and chief data officer Nick Mason have stepped back from their duties.
The Prime Minister had faced demands from within the party to act on the candidates over concerns the issue was further damaging the Conservatives’ electoral chances.
Following the decision to pull support, Tory peer and former Brexit secretary Lord Frost said: “We get there in the end.
“But why did it take so long to come to a decision that seemed so necessary right from the start?”
Northern Ireland minister Steve Baker called for those who placed bets on the election date to be suspended by the party on Monday night, saying “the Prime Minister would have to answer” for why he had not acted by then.
“The Conservatives who sought to line their own pockets by betting on the election date are not fit to be candidates for Parliament.
“Rishi Sunak now needs to come clean with voters across the country and tell them exactly how many of his Conservatives are implicated and who they are.”
Liberal Democrat deputy leader Daisy Cooper said: “This should have happened immediately when these scandalous revelations emerged, but instead Rishi Sunak has dithered and delayed.”
Labour administratively suspended Central Suffolk and North Ipswich candidate Mr Craig after it emerged he was facing a Gambling Commission investigation.
Mr Craig said he “deeply” regretted putting “a bet on the Tories to win here” but said it was done “with the intention of giving any winnings to local charities”.
“I will comply fully with the investigation,” he added.
Meanwhile the Met said it was “simply untrue” to say the force had leaked the names of people suspected of using inside information to bet on the July 4 date.
A source close to the Cabinet Office told the Daily Telegraph the Gambling Commission is telling the Met “and then almost instantly these names are finding their way to journalists”.
A Met spokesman said: “The allegations that the Met has leaked information are simply untrue.”