The collapse of Silicon Valley Bank (SVB) marked the first “social media, internet-based bank run” in U.S. history, Sen. Mark Warner (D-Va.) said Thursday. 

During a Senate Finance Committee hearing, Warner placed blame on venture capitalists and other depositors at the bank for coordinating their bank withdrawals over social media and online group chats.

That all but ensured that SVB would go under, Warner said.

“I’ve been supportive of the venture capital community — I was a venture capitalist before — but I think there were some bad actors in the VC community who literally started to spur this run by virtually crying fire in a crowded theater in terms of rushing all these deposits out,” Warner said. 

“I’m not sure what regulatory system anywhere, no matter how much capital and how many stress tests that would have protected any institution from a $42 billion bank run in a single day,” he added. 

SVB depositors rushed to withdraw their funds following the bank’s announcement that it needed to raise capital. SVB faced huge unrealized losses on its long-term treasury bonds and other investments that lost value due to the Federal Reserve’s interest rate hikes.

Treasury Secretary Janet Yellen told Warner that she and federal regulators agreed to guarantee SVB deposits to bolster confidence in the banking system and ensure that more banks were not susceptible to a similar bank run.

“No matter how strong capital and liquidity supervision are, if a bank has an overwhelming run that’s spurred by social media or whatever so that it’s seeing deposits flee at that pace, the bank can be put in danger of failing,” Yellen said. 

Warner was one of 17 Senate Democrats who voted for a 2018 bill to loosen regulations on mid-sized banks. Progressives have blamed the law for spurring on the recent bank failures. The two banks that collapsed — SVB and Signature Bank — aggressively lobbied for the bill. 

Warner has defended his decision, arguing that mid-sized banks “needed some regulatory relief” in a Sunday interview with ABC.