Ted Cruz accuses Donald Trump of spreading rumours about his marriage

Ted Cruz accused Republican presidential rival Donald Trump of stoking false rumours about his personal life on Friday, charging that the billionaire businessman and Republican front-runner was trafficking in "sleaze" and "slime."

Speaking to reporters in Wisconsin, Cruz said the campaign has taken a "darker turn." He accused Trump and "his henchmen" of spreading untrue rumours on social media and in a supermarket tabloid that Cruz cheated on his wife, Heidi.

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"Trump demonstrated that when he's scared, when he's losing, his first and natural resort is to go to sleaze and to go to slime," Cruz said.

He added, "He's willing to attack anyone and everyone. And truth has nothing to do with it."

Trump responded Friday in a statement saying he had nothing to do with the story published this week by the National Enquirer.

"I have no idea whether or not the cover story about Ted Cruz in this week's issue of the National Enquirer is true or not, but I had absolutely nothing to do with it, did not know about it and have not, as yet, read it," he said.

But Trump also noted that the tabloid has been right about several major stories, including allegations that former Democratic presidential candidate John Edwards had had an affair and a child with a woman who wasn't his wife.

'Stories have been swirling': ex-Trump staffer

The Cruz story published this week in the tabloid described what it called rumours, providing no evidence that Cruz had engaged in an extramarital affair. The only source quoted by name was a former Trump campaign adviser, Roger Stone, who said such "stories have been swirling around Cruz for some time" without offering any evidence they are true.

The accusations are an escalation of the back-and-forth between the two candidates that began this week, when Trump tweeted that he might "spill the beans" about Heidi Cruz. The tweet was in response to an advertisement from an outside group opposed to Trump's candidacy that featured a risqu photo of Trump's wife, Melania.

Cruz, on his Facebook page on Friday, accused Trump, who hasn't held a public event since Monday, of "hiding in Trump Tower" and campaigning by Twitter instead of holding events with voters.

Asked if he plans to vote for Trump if he becomes the party's nominee, Cruz said, "I don't make a habit of supporting people who attack my wife and my family."