Donald Trump wasn’t happy to hear that Bruce Springsteen hasn’t backed down from calling him an “unfit president” as he performs in Europe, so he went on another rant on social media overnight Sunday, demanding a “major” investigation be launched against the rock ‘n’ roll legend for singing at a Kamala Harris rally in October.

Bruce Springsteen has called out Donald Trump–again–after the president called the music icon, 75, a “dried out prune” and “highly overrated.” Springsteen and the E Street Band are in the UK and Europe,