BitcoinBTC -1.2%, ethereum and other major cryptocurrencies are braced for extreme volatility after Circle’s $43 billion USDCUSDC 0.0% stablecoin lost its U.S. dollar peg—topping off a wild week for crypto.

The bitcoin price has sunk by 10% this week due to the failure of the crypto-friendly bank Silvergate, wiping away $100 billion from the combined crypto market as the price of top ten cryptocurrencies ethereum, BNBBNB +0.9%, XRPXRP +3.8%, cardano, dogecoin, polygon and solana go into freefall.

Now, the crisis at startup lender Silicon Valley Bank (SVB), where stablecoin issuer Circle held a part of its USDC cash reserves, is threatening to wipe out the second-largest stablecoin by market capitalization.

“Silicon Valley Bank is one of six banking partners Circle uses for managing the ~25% portion of USDC reserves held in cash,” Circle posted to Twitter, exacerbating a near-10% drop from its U.S. dollar peg. “While we await clarity on how the FDIC receivership of SVBVB -3% will impact its depositors, Circle and USDC continue to operate normally.”

Circle has $3.3 billion of the $40 billion backing its stablecoin was deposited at SVB. SVB deposits of up to $250,000 are guaranteed by the Federal Deposit Insurance Corporation (FIDC), potentially leaving Circle and other depositors out of pocket.

“FIDC deposits are only insured up to $250,000 and when there is a bank run, depositors might lose out,” Markus Thielen, head of research and strategy at Matrixport, said in an emailed note.

In a further blow, major U.S. crypto exchange CoinbaseCOIN -8%, which issues USDC through a joint venture with Circle, announced it has suspended U.S. dollar USDC conversions, posting to Twitter it would “temporarily” pause the conversions while banks are closed over the weekend.

“Circle is currently protecting USDC from a black swan failure in the U.S. banking system,” Circle chief strategy officer Dante Disparte posted to Twitter. “Silicon Valley Bank is a critical bank in the U.S. economy and its failure—without a Federal rescue plan—will have broader implications for business, banking and entrepreneurs.”

California-based SVB was taken over by regulators and shut down on Friday after panic spread among depositors who yanked around $40 billion from the bank and efforts to raise fresh capital failed.

The bank’s woes are thought to have begun when the U.S. Federal Reserve began hiking interest rates last year, wiping out the value of its mortgage bonds and US Treasuries. This week, Fed chair Jerome Powell told lawmakers he sees interest rates rising past market expectations this year.

Meanwhile, Circle’s banking problems, adding to the crypto crisis sparked by the collapse of Silvergate earlier in the week, have caused bitcoin transaction fees to spike as traders frantically try to secure their crypto.

“Bitcoin network transaction fees are very high and are indicating panic,” Thielen said, adding the largest stablecoin tether has managed to hold its dollar peg for now.

“From the three major stablecoins, we now have one standing and of course, that’s the big one. Tether’s USDTUSDT -0.2% which has weathered the Paxos-Binance BUSDBUSD -0.3% storm in February and is also now weathering the Circle USDC storm.”