WATCH: Donald Trump says he'd 'love to punch' protester at Nevada rally

THIS is the moment Donald Trump mocked a left-wing protester, telling supporters: "I'd love to punch him in the face."

The outspoken billionaire made the comment after the activist was kicked out of a packed rally for causing trouble.

He branded the political opponent "nasty as hell", saying: "There's a guy totally disruptive, throwing punches.

"We're not allowed to punch back any more. I love the old days."

   BRASH: Donald Trump made the comment to fans in Nevada

Trump, who is running for the Republican candidate for President, praised the security guards who took the man out without hurting him.

He said: "It's true. You know I love our police and I really respect our police and they're not getting enough.

"They're not. Honestly I hate to see that. Here's a guy throwing punches."

   RIVAL: Hillary Clinton won the state's Democratic caucus last month

Trump, 69, was speaking ahead of this morning's Republican caucus vote in Nevada.

The businessman, who sparked outrage after calling for Muslims to be banned from entering the US, is the clear front-runner in the state.

Former First Lady Hillary Clinton narrowly won the Democratic caucus in Nevada last week, picking up 52.6% of the vote.