Story highlights "We need a commander in chief, not a Twitterer in chief," Cruz told reporters

Cruz then added that Trump's tweets on Wednesday morning

Goffstown, New Hampshire (CNN) Ted Cruz lashed into Donald Trump here on Wednesday for nearly 10 minutes, saying he's a sore loser and a temperamental man who was behaving more immaturely than Cruz's grade-school children.

"We need a commander in chief, not a Twitterer in chief," Cruz told reporters, dubbing his rival's outbursts on social media as "Trumper-tantrums." "Donald's insults get more and more hysterical the more and more upset he gets."

Cruz added, "We're liable to wake up one morning, and Donald, if he were president, would have nuked Denmark."

Trump on Wednesday morning charged that Cruz "stole" his victory in Iowa by sending out controversial campaign mailers and using a CNN report to claim that Ben Carson had dropped out of the race when, in fact, the report said Carson was only heading to Florida for a quick break and to pick up clothes.

Cruz, reacting hours later to Trump's calls for an entirely new election in Iowa, added that Trump's tweets on Wednesday morning showed no more maturity than Cruz's two young daughters, aged 5 and 7.

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