Elon Musk, the world’s richest man, blamed fellow billionaires George Soros, Reid Hoffman and the ActBlue fundraising organization over recent protests targeting his firm Tesla, citing an “investigation”—though it’s unclear what investigation he’s referencing.

Elon Musk, never one to shy away from controversy, has fired off yet another explosive tweet—this time claiming that a coordinated attack against Tesla is being orchestrated by groups allegedly funded by ActBlue,