The hackers recently claimed to have gotten in to Trump's voicemail, leaking messages from the media and supporters, Gawker reported earlier this month.

>>Read more trending news

Not only are they going after Trump's campaign, they are also going to try to sabotage his brand, according to reports.

They threatened to bring down the official website for Trump Tower in Chicago on April 1, The Mirror reported.

Calling the online attack #OpTrump, the group said, "This is a call to arms. This is a call to the freedom fighters, to the forgotten, to the censored. To our fellow hacktivists throughout the world, this is a call to protect our future, our freedom and our very way of life. This is a call to you."

The threat wraps up with, "This is not a warning. This is a declaration of total war. Operation Trump engaged. We are Anonymous. We are legion. We do not forgive. We will not forget. Donald Trump, it is too late to expect us," The Mirror reported.