Ontario Progressive Conservative Leader Patrick Brown has resigned under pressure from his caucus just hours after allegations emerged that he had inappropriate sexual relations with teenage girls.

His shocking fall in a few short hours leaves the party without a leader four months before an election that the PC party was favoured to win according to recent polls. Mr. Brown was forced out by senior party members after initially saying he would remain as leader while defending himself against allegations of misbehaviour during his time as a federal MP.

The Globe has learned from multiple party sources that caucus members held two conference calls just before midnight Wednesday and demanded that Mr. Brown resign. He agreed to the request on the call. At 1:30 am he released a statement.

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"These allegations are false and have been difficult to hear. However, defeating Kathleen Wynne in 2018 is more important than one individual," the statement read.

"For this reason, after consulting with caucus, friends and family I have decided to step down as Leader of the Ontario PC Party. I will remain on as a MPP while I definitively clear my name from these false allegations."

Ontario Progressive Conservative leader Patrick Brown resigned overnight Wednesday when allegations of sexual misconduct emerged. Brown had originally vowed to stay on as leader, but caucus pressure saw him resign a few hours later.

The scandal is the latest in a global Me Too reckoning that has toppled high profile men accused of sexual misconduct in several industries, from film to politics. Mr. Brown, 39, was the second Canadian leader to fall Wednesday. Nova Scotia's Progressive Conservative leader Jamie Baillie was asked to resign his post Wednesday morning after an investigator hired by the provincial PC Party to probe "allegations of inappropriate behaviour" found he had breached workplace harassment rules.

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The timing of Mr. Brown's departure gives the PC party little opportunity to recover before Ontario goes to the polls in June. The opposition party had been leading Premier Kathleen Wynne's Liberals in popular support. Politically active since his youth, Mr. Brown, who is single, was seen as the party's best hope of ending the Liberals 14 years in power.

It took less than four hours to radically reshape the province's political landscape. Reporters were summoned to Queen's Park for a news conference at 9:45 p.m., just minutes before CTV News aired a report alleging sexual misconduct involving two young women. A visibly upset Mr. Brown vowed he was innocent and would stay on to fight, saying he was made aware only hours earlier by CTV News that the network was ready to report the allegations.

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"A couple of hours ago, I learned of troubling allegations about my conduct and character. And I'm here tonight to address them. First, I want to say these allegations are false. Categorically untrue. Every one of them," he said.

Brown abruptly left the podium and ignored a throng of journalists who followed him to a waiting vehicle outside. When asked if he would comment further, he replied "I'll be at work tomorrow."

But as he drove away, his inner circle was already disintegrating. Members of his campaign team and office staff announced they were stepping down because Mr. Brown had rejected their advice that he resign for the sake of the party. As the scandal began to gain international attention, senior party members organized emergency phone calls to tell Mr. Brown they would not support him.

Premier Kathleen Wynne did not initially offer comment Wednesday night on the allegations or Mr. Brown's response. However on Twitter, she wrote: "It's a difficult and brave thing to do to come forward in the way these young women have done tonight. My government and I have been clear on the issue of sexual harassment and assault. In fact our policy and our ad were called "It's Never Okay."

Andrea Horwath, leader of the third-party NDP, was quick to call for Mr. Brown to step down.

Ms. Wynne held a press conference in her Queen's Park office Thursday morning, during which she called the allegations against Mr. Brown "shocking." While she would not comment on whether Mr. Brown should resign his seat in the legislature, the Premier said the allegations against the former opposition leader were a sign of Ontario's continuing struggle with issues of sexual harassment.

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"I did watch the story last night and I would say to those young women that they were very brave and I acknowledge that it was very courageous for them to step forward. I would also say to them that I hope that they will find the supports that they need," she said. As for Mr. Brown, she added that the "political fallout will be the political fallout" for him.

The Premier also ruled out moving the election date, which will leave the Tories with just over four months to prepare.

Mr. Brown's colleagues also began to post public statements when they knew his resignation was imminent.

Caroline Mulroney, one of the party's star candidates who is running in York-Simcoe, posted that "we are living in a powerful moment where women and girls across Ontario, across Canada and around the world are ending their silence ..."

She added "when we hear allegations, we must listen. We must make sure these injustices are never tolerated, and that we respect and honour the brave women we are hearing."

Early Thursday morning, the PC caucus unanimously agreed that Mr. Brown had to go as leader.

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"Mr. Brown is entitled to a legal defence and due process, but he cannot lead us into an election as a result of these allegations. The Ontario PC Caucus unequivocally upholds the principle that a safe and respectful society is what we expect and deserve," announced the group of 29 MPPs in a statement.

The party is expected to hold a caucus meeting Thursday to elect an interim leader. In an e-mail to the party's legislators, PC Party president Rick Dykstra says he has requested an interim leader be selected, and MPPs have agreed.

Dykstra says that interim leader will serve until a new leader is picked in a leadership election, according to the party's constitution. It's not clear from Dykstra's message when that leadership election will take place.

Sources tell The Canadian Press that PC deputy leaders Sylvia Jones and Steve Clark are expected to hold a press conference later Thursday.

The political shakeup was caused by an exclusive report by CTV News about Mr. Brown's interactions with two young girls several years ago. The news agency reported that one girl, a high-school student in Barrie at the time of the incident, alleges that she met Mr. Brown at a local bar with a mutual friend. The future PC Leader invited her to his home and provided them with alcohol, though they were underage. During a tour of his home, he stopped in his bedroom with her and then exposed himself and asked her to perform oral sex on him, CTV News reported. She did briefly and then left.

The other woman, a former employee of Mr. Brown, alleges that she was sexually assaulted in 2013 after a charity event in Barrie. After a night of heavy drinking, she told CTV News that Mr. Brown pushed her down on his bed and forcibly kissed her.

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The woman said she met Mr. Brown on a flight in 2012. Mr. Brown later tracked her down via her Facebook profile and sent her his phone number and allegedly told her to contact him if she needed to get past lineups into bars – she was also not of legal drinking age at the time.

In March 2013, the woman said Mr. Brown hired her to work in his constituency office. She alleged to CTV that after a hockey charity event that she helped organize, she attended a party with Mr. Brown and his friends. She was intoxicated and went to Mr. Brown's home with some of his friends after the bar closed.

During the evening, she said she was invited to Mr. Brown's bedroom with a friend to look at pictures. When the friend left the room, Mr. Brown and the woman were sitting on his bed. She said that without invitation, he forced her back and kissed her. She says she was unresponsive to his kisses. He then climbed on her and continued to kiss her. She told him to stop and said she had a boyfriend. He then drove her to her parent's home.

"I felt it was sexual. I could feel his erection on my legs when he was on top of me so I felt that it would have gone to sexual intercourse if I had not done anything," the woman told the news agency. "I would characterize that as a sexual assault."

CTV did not identify the women. The Globe and Mail was unable to reach the women or verify their allegations.

After Mr. Brown's press conference on Wednesday, his campaign manager, chief of staff and deputy campaign manager announced they were resigning.

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"Earlier today, all three of us became aware of allegations about Patrick Brown. After speaking with him, our advice was that he should resign as PC Party Leader. He did not accept that advice. Since our view is that this advice was in the best interest of the PC Party, we have therefore resigned our positions," they announced.

Federal Conservative Leader Andrew Scheer said in a statement that sexual misconduct and harassment have no place in Canadian society or politics.

But he stopped short of calling for Mr. Brown to step down amid the allegations.

"I understand how difficult it can be for women to come forward under these circumstances," Mr. Scheer said.

"The allegations against the Leader of the Ontario Progressive Conservatives are extremely serious and should be investigated fully."

With a report by Adam Radwanski

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