Republican frontrunner Donald Trump warned his supporters to be vigilant as the Nevada caucuses got underway Tuesday evening.

“Make sure you get on the Trump line and are not mislead by the Cruz people. They are bad! BE CAREFUL,” the businessman tweeted.

Trump’s tweet came as Ted Cruz faces scrutiny for his tactics on the campaign trail. The Texas senator was heavily criticized in Iowa after he relayed a CNN report to supporters suggesting Ben Carson would drop out of the 2016 race. This week, Cruz was forced to fire his communications director for circulating a video that falsely accused Marco Rubio of mocking the bible.

Cruz has maintained throughout it all that his campaign will be about the issues the American people face and not personal insults.

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