Boris Johnson’s bid to become the U.K.’s next prime minister was thrown into turmoil after an argument with his partner prompted police to visit his London residence. 

Officers were called to the home Johnson shares with Carrie Symonds shortly after midnight on Friday, six hours after he was confirmed as the front-runner in the race to succeed Theresa May.

Police said they found no cause for action as both Johnson and Symonds were safe and well after a neighbour raised concerns for her safety. But the incident dominated Saturday’s U.K. newspapers and threatened to damage Johnson’s campaign at a critical time in the Conservative Party leadership contest.

On Saturday, Johnson was asked several times by journalist Iain Dale in front of an audience of Tory party members on whether the incident meant he’s fit to become prime minister. The audience booed Dale for pressing the front-runner, and cheered Johnson when he dodged the question.

"Most people would rather judge my ambition and character by my program," Johnson said.

Foreign Secretary Jeremy Hunt, his only remaining rival in the contest, also appeared at the event in Birmingham, England. 

Hunt wrote to Johnson on Friday evening before the altercation became public effectively accusing him of hiding from questions and avoiding media scrutiny. This latest incident will make that more difficult for the former London mayor as reporters are now staked out on his doorstep.

"Scrutiny can be uncomfortable," Hunt wrote in the letter released to the media. "But if we can’t handle it with friends, we won’t deserve to lead against our opponents."

The Tory leadership election is a pivotal moment for Britain, with the two candidates due to spend the next few weeks at more than 15 similar events, known as hustings, as they battle for the votes of 160,000 grassroots members of Tory party.

The winner will have the chance to re-shape the country’s politics, and could dramatically alter its exit from the EU, which is due to take place in four months. For the EU, the prospect of a Johnson victory would be their worst nightmare. Many European officials blame Johnson for Brexit -- he led the 2016 referendum Vote Leave campaign -- and regard him as a dishonest populist intent on wrecking the bloc.

With assistance by Kitty Donaldson