Donald Trump threatens to 'spill the beans' on Ted Cruz's wife

After seeing his wife, Melania, in a Ted Cruz ad, Donald Trump threatened Cruz's wife.

Raising the stakes in an already bitter battle, Donald Trump threatened Ted Cruz's wife in a cryptic tweet, saying he would "spill the beans" on her.

Mr Trump appears to be referencing an advertisement done by the Make America Awesome Politcal Action Committee -- not Mr Cruz's campaign -- that showed Melania Trump posing naked with the words "Meet Melania Trump, your next first lady. Or you could support Ted Cruz on Tuesday."

Mr Cruz responded shortly after, saying that his team had nothing to do with the ad. He warned Mr Trump that his wife is off-limits.

It is unclear exactly about what Mr Trump could "spill the beans" on Mr Cruz's wife, Heidi, but the Republican front-runner has shown he will strike opponents with low-blows. He and Mr Cruz have engaged in increasingly aggressive rhetoric as the Republican field has been whittled down.

As seen in the above tweet, Mr Trump has taken to calling Mr Cruz "lyin' Ted", which Mr Cruz has encouraged all non-Trump voters to coalesce around him.

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