The People’s Bank of China injected 348 billion yuan, or about $52 billion, into the banking system through overnight reverse repos in what was described as its first mid-month injection of this kind. Reverse repos are a short-term liquidity tool used by central banks to add cash to financial institutions, typically to steady money-market conditions and manage funding needs. The move stands out because it was characterized as the first such mid-month operation in history, suggesting an unusual timing decision as authorities sought to support liquidity.