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Donald Trump is under fire for a series of tweets he sent out in the early hours Friday morning.

Tweeting at 3:20am ET, Trump took aim at "Crooked Hillary," the dishonest media and former Miss Universe Alicia Machado, who he called "disgusting" and a "con."

Critics have said that Trump should be focused on reaching out to undecided voters, not engaging in personal attacks with anyone he believes has insulted him.

Hillary Clinton herself took to Twitter to respond to Trump's "tweet storm":

The Republican nominee, however, is not backing down.

In yet another tweet, this one sent out Friday afternoon, Trump wrote, "For those few people knocking me for tweeting at three o'clock in the morning, at least you know I will be there, awake, to answer the call!"

What do you think about Trump's statements on Twitter? Let us know in comments.

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