Tech billionaire Elon Musk signaled Monday that he will be looking into Fort Knox, where the United States has a massive and heavily secured gold reserve.

“Looking for the gold at Fort Knox …” Musk wrote on the social platform X.

He also shared a post from Sen. Mike Lee (R-Utah) on X, in which the senator said he has been denied access to Fort Knox, an Army installation in Kentucky.

“Who is confirming that gold wasn’t stolen from Fort Knox? Maybe it’s there, maybe it’s not. That gold is owned by the American public! We want to know if it’s still there,” Musk said.

A series of social media exchanges between Elon Musk and others has ignited public discussion about the gold reserves at Fort Knox, which reportedly haven’t been audited since 1974. The conversation began when Zero Hedge’s X account suggested that Musk “take a look inside Fort Knox” to verify the reported 4,580 tons of US gold reserves, prompting Musk to question whether the reserves weren’t reviewed annually.