(CNN) President Donald Trump's appointee to a Department of Energy post says inflammatory comments that appeared to have been made by him online were the result of "cyber attacks and Internet crimes" committed against him over the past several years by "imposters in social media."

William C. Bradford, Trump's appointee to head the Energy Department's Office of Indian Energy, made the claim in response to significant evidence uncovered by CNN's KFile that suggests an account on the online commenting service Disqus belongs to him. The account was made private earlier this year but is linked to Bradford through the Google cache. The user commented on articles written by Bradford and made clear references to being the author of the articles. In one comment, the account directed a fellow commenter to contact him at Bradford's email address and phone number.

Many of the comments left by the account mirror what Bradford has said publicly. The user also made multiple references to joining the Trump administration and referenced key details that match up with Bradford's biography.

In the comments section of a September 2016 article on the conservative new site Daily Wire, the Disqus user wrote : "Well, it is a fact: Obama is the son of a fourth-rate p&*n actress and w@!re." The comment is an apparent reference to an unfounded right-wing conspiracy that Obama's mother posed for nude photos and perhaps a reference to Philippine President Rodrigo Duterte calling Obama a "son of a whore."

Bradford told CNN's KFile in an email from his personal account on Monday: "I cannot comment on an ongoing federal investigation into multiple cyber attacks and Internet crimes committed against me over the past several years, to include email intrusions, hacking, and impostors in social media."

A spokesperson for the FBI declined to comment. Representatives from the Department of Energy also declined to comment.

Bradford received national media attention in 2015 when he resigned as professor at West Point after publishing a paper arguing for the US military to target Islamic holy sites as part of the war on terror and advocating for a group of scholars to be treated as enemy combatants. Prior to joining the administration, he served as attorney general of the Chiricahua Apache Nation and a professor of "American Indian law and policy as well as national security law and strategy," according to his online biography at the Department of Energy's website.

After his appointment by the Trump administration to the Department of Energy, the Washington Post in June unearthed inflammatory comments Bradford made on Twitter, including calling Obama a Kenyan and saying that the World War II-era internment of Japanese Americans was necessary. Bradford apologized for the comments in a statement to the Washington Post, calling them "inexcusable."

Bradford's appointment did not require congressional approval. In his role, he is responsible for maximizing "the development and deployment of energy solutions for the benefit of American Indians and Alaska Natives," according to the department's website.

In another comment from January 2016, the Disqus account propagated the debunked claim that Obama's birth certificate was a fake and included a photoshopped picture of the former president's birth certificate.

"As you can see, it is easy to manufacture a birth certificate, but Obama has never allowed anyone to review the alleged piece of paper the PDF file is based upon, and Hawaii officials admit there is no such paper," the user wrote. "Here is a manufactured 'birth certificate' showing the Obama was in fact one of three triplets born that day in Hawaii."

In a follow-up comment, the account said Obama was born in Kenya and referenced a far-right conspiracy theory that Obama's real father was a family friend named Frank Marshall Davis.

"With that said, there is also no doubt that Obama was either not eligible because his father was Obama Sr, and thus Obama did not have two US citizen parents, or Obama's father was Frank Davis, but Obama was born in Kenya," the user said. "The 'birth certificate' released online 5 years ago is an obvious fake, and every intellectually honest person knows that. It was probably created to cover up the fact that his mother, Stanley Dunham, had an affair with Frank Davis and tried to fool Obama Sr by having the baby in Kenya."

As recently as this January, Bradford himself said in a radio interview that he was "agnostic" on whether Obama was an American citizen and repeated the claim that his birth certificate was a fake.

"I am an agnostic on whether the previous President was born in the United States because I simply don't know," Bradford said on an online radio show called Civilization Jihad Awareness. "He's never produced an actual birth certificate. He may well be an American citizen, he may have been born in the United States, but the document that was posted up online is not a real birth certificate, it's a PDF file in multiple layers and we have no idea."