U.S. President Donald Trump’s revenge campaign is continuing apace, with celebrities who backed his 2024 election opponent Kamala Harris now in his sights.

The Republican leader launched a blistering tirade against legendary rocker Bruce Springsteen last week, calling him “not a talented guy” and attacking his physical appearance, after the New Jersey icon — who endorsed Harris last year — branded the Trump administration “corrupt, incompetent and treasonous” during a concert in England.

Now Trump is demanding a “major investigation” into Harris’ lengthy list of celebrity endorsements, singling out Springsteen as well as Beyoncé, Oprah Winfrey and Bono, and claiming they were illegally compensated.

“Candidates aren’t allowed to pay for ENDORSEMENTS, which is what Kamala did, under the guise of paying for entertainment,” Trump fumed in a caps lock-heavy screed on social media in the early hours of Monday.

“This was a very expensive and desperate effort to artificially build up her sparse crowds. IT’S NOT LEGAL!” he added, calling the various artists who came out in support of Harris “unpatriotic.”

Then-Vice President Harris received a steady stream of celebrity backers leading up to the November election. Beyoncé spoke at a rally in Houston along with former Destiny’s Child bandmate Kelly Rowland, but did not perform, while Winfrey hosted a star-studded, live-streamed town hall near Detroit.

Rumors falsely circulated that the superstars were paid millions for their support, which their teams quickly shut down.

The Harris campaign, which raised more than $1 billion in just a few months, paid Beyoncé’s production company $165,000 and gave $1 million to Harpo Productions, Winfrey’s company, according to campaign finance records.

Winfrey addressed criticism over the figure in a social media post, saying she did not receive “any personal fee.”

“However, the people who worked on that production needed to be paid. And were. End of story,” she wrote on Instagram.

Beyoncé’s mother said the Grammy-winning artist “did not receive a penny” for her endorsement either and slammed the speculation as fake news. Harris often made her campaign rally entrances to Beyoncé’s song “Freedom.”

Trump himself has courted celebrity endorsements in all three of his presidential campaigns, from Kanye West to Kid Rock, with the latter taking the stage at the Republican National Convention and Trump’s inauguration-eve victory rally.