Social media-fueled rumors about banks collapsing are popping up at an unprecedented frequency in China, forcing regulators and even the police to step in to calm depositors.

Just since the past month, worried savers have descended on three banks to withdraw funds amid rumors of cash shortages that were later dismissed as false. Over the weekend customers rushed to a bank in the northern Hebei province to take out money, prompting local regulators to publicly vouch for the soundness of its lenders as the police halted the run.

Confidence in the $43 trillion banking system is eroding among the nation’s more than 1 billion account holders, threatening a cornerstone of China’s rise into an economic powerhouse. After several bailouts and the first bank seizure in more than two decades last year, the coronavirus outbreak and its economic fallout have exacerbated an already shaky situation in the world’s largest banking system.