Former Secretary of State Colin Powell bashed Donald Trump as a "national disgrace" and an "international pariah," criticized Hillary Clinton's response to the controversy surrounding her email server and called the lengthy investigation into the 2012 Benghazi attacks a "witch hunt" in private emails from earlier this year that were leaked Tuesday.

The emails, first reported by BuzzFeed , came from the website DCLeaks.com, a site that has ties to the Guccifer 2.0 hacker behind the breach of the Democratic National Campaign's accounts and who the FBI believes has ties to Russia.

Powell, who served during President George W. Bush's first term, confirmed the authenticity of the emails to Buzzfeed and NBC News, adding, "the hackers have a lot more."

In a June 17 email to a former aide, Powell said the Republican presidential nominee is a "national disgrace" who "is in the process of destroying himself, no need for Dems to attack him. [Speaker of the House] Paul Ryan is calibrating his position again."

Two months later, he wrote to the same aide calling the "birther" movement questioning President Barack Obama's citizenship, stoked by Trump, is "racist."

"That's what the 99% believe," Powell wrote on Aug. 21. "When Trump couldn't keep that up he said he also wanted to see if the certificate noted that he was a Muslim."

"As I have said before, 'What if he was?' Muslims are born as Americans everyday," he added.

In the same email, he scoffed at Trump's decision to bring in Roger Ailes, the former chair of Fox News who departed the network last month amid numerous allegations of sexual harassment, as an adviser to his campaign.

"And Ailes as an adviser won't heal women, don't you think," Powell wrote, in reference to Trump's low poll numbers with women voters.

In a different email, Powell lamented Clinton's defense of her use of a private email server, which she has often tried to excuse by comparing it to Powell's set-up. Powell, who used private email but did not have a personal server in his home, has expressed annoyance at Clinton's involving him in the story, but did offer her advice on personal communications when she was newly installed at the State Department.

In new emails revealed by DNCLeaks, Powell complained that the Democratic nominee had mishandled the controversy by using him as an excuse.

"Sad thing … HRC could have killed this two years ago by merely telling everyone honestly what she had done and not tie me to it," Powell wrote of Clinton on Aug. 28. "I told her staff three times not to try that gambit. I had to throw a mini tantrum at a Hampton's party to get their attention. She keeps tripping into these 'character' minefields."

To another friend, Powell wrote : "They are going to dick up the legitimate and necessary use of emails with friggin record rules. I saw email more like a telephone than a cable machine. As long as the stuff is unclassified. I had a secure State.gov machine. Everything HRC touches she kind of screws up with hubris."

But he also said the repeated investigations into the 2012 attack on a diplomatic compound in Benghazi, Libya – during the probe of which the existence of Clinton's server became public knowledge – was overblown.

"Benghazi is a stupid witch hunt," he wrote to his successor, former Secretary of State Condoleezza Rice, in December 2015.

In the email, he blamed Ambassador Chris Stevens, who was killed in the attack, for getting careless, but also blamed Clinton's State Department.

"Basic fault falls on a courageous ambassador who thoughts Libyans now love me and I am OK in this very vulnerable place," he wrote to Rice. "But blame also rests on his leaders and supports back here. Pat Kennedy, Intel community, [the Diplomatic Security Service] and yes HRC."

In emails to Powell, Rice was similarly unsparing to Powell's Cabinet colleague, former Secretary of Defense Donald Rumsfeld, for the way his department handled the Iraq War.

"First, we didn't invade Iraq to bring democracy – but once we overthrew [Iraqi President Saddam Hussein], we had a view of what should follow," Rice wrote in mid-2015. "If Don and the Pentagon had done their job (after claiming the rights to lead post-war rebuilding—things might have turned out differently)."

"Don should just stop talking," she added. "He puts his foot in his mouth every time."