(CNN) Donald Trump's newly minted convention manager on Sunday accused Republican presidential rival Ted Cruz's campaign of "Gestapo tactics" and of "not playing by the rules" in its efforts to wrangle the support of Republican delegates.

Paul Manafort, a veteran Republican operative who managed the convention efforts of several successful presidential campaigns, was tasked earlier this week by Trump with directing the campaign's new delegate-focused campaign strategy.

Manafort said the Trump campaign's strategy won't involve threatening delegates, but accused Cruz of employing those tactics, which he referenced by alluding to the notorious Nazi Germany secret police force.

"He's threatening," Manafort said of Cruz on NBC's "Meet the Press." "You go to these county conventions, and you see the tactics, Gestapo tactics, the scorched-earth tactics."

Trump on Sunday tweeted, "I win a state in votes and then get non-representative delegates because they are offered all sorts of goodies by Cruz campaign. Bad system!"

I win a state in votes and then get non-representative delegates because they are offered all sorts of goodies by Cruz campaign. Bad system! — Donald J. Trump (@realDonaldTrump) April 10, 2016

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