A defiant Donald Trump on Sunday threatened to imprison Hillary Clinton if he wins the White House in a vicious presidential debate that included disputes on Middle East affairs and taxes.

Their debate, the second of three before the Nov. 8 vote, was remarkable for the brutal nature of the exchanges between Trump, the Republican presidential nominee, and Clinton, his Democratic rival.

He called her a “devil” who repeatedly lies, someone with tremendous hate in her heart. She called him an abuser of women.

Through it all, Trump, 70, and Clinton, 68, both landed punches as they clashed over taxes, healthcare, U.S. policy in the Syria civil war and Clinton’s comments that half of Trump’s supporters belonged in a “basket of deplorables.”

Trump took the stage in St. Louis, Missouri, at the most perilous time of his 16-month-old candidacy.

A newly uncovered 2005 video of him making vulgar remarks about women prompted a stampede of Republican politicians to abandon him, deepened fissures with establishment party figures, and seemed to many in the party to put his already uphill battle to win the White House even farther out of reach.

President Barack Obama’s former attorney general, Eric Holder, led the condemnation against Trump’s threats to imprison Clinton, describing the Billionaire businessman as “dangerous/unfit” and pointing out that even president Richard Nixon’s top lawyer resigned when ordered to probe a political opponent.

A U.S. president does not normally order the legal or criminal investigation of individuals.

Former U.S. ambassador to Russia Michael McFaul tweeted that the comment “reminds me of autocracies I study. Embarrassed this is happening in America.”

Nobel Prize winning economist Paul Krugman said: “Let’s be clear: a candidate for president promised to put his opponent in jail if he wins. Everything else is secondary.

On Syria and in a startling admission, Trump dismissed a statement from his vice presidential running mate, Mike Pence, last week in which Pence said the United States should be prepared to intervene militarily in Syria.

“He and I haven’t spoken, and I disagree,” Trump said.

As for Clinton, she said ground forces in Syria would be a “serious mistake.”

She also vowed to investigate Russia for war crimes over Syria.

As in the first debate, she laid a series of traps for Trump, prodding him toward admitting he had not paid federal income tax in around two decades.

With his campaign in a tailspin, Trump apologized for “locker room talk” in which he bragged about groping women, but stated baldly that “Bill Clinton was abusive to women.”

“If you look at Bill Clinton, far worse,” Trump insisted. “Mine are words, his was action,” he said.