Story highlights "Donald, you're a sniveling coward and leave Heidi the hell alone," Cruz said

Trump inserted Heidi Cruz into the race when he tweeted Tuesday night that the Texas senator should "be careful" or he would "spill the beans on your wife"

Washington (CNN) An angry and emotional Ted Cruz on Thursday ripped into Donald Trump for his attacks on Cruz's wife, Heidi, and repeatedly declined to say whether he would support Trump if he's the Republican presidential nominee.

"Donald, you're a sniveling coward and leave Heidi the hell alone," Cruz told reporters after a factory tour in Dane, Wisconsin, pointing his finger at the cameras for emphasis.

Asked then multiple times if he could still support Trump in November as the Republican nominee given his most recent comments, a fired-up Cruz paused for a few beats before not directly answering whether he would.

"I'm going to beat Donald for the nomination," Cruz responded, before saying three times: "Donald Trump will not be the nominee."

Even as tensions escalated between the two, Cruz has insisted that he would back Trump if he won the nomination because he pledged he would do so at the outset of the Republican race. Cruz spent much of the campaign praising Trump, at one point calling him "fantastic."

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