BEIJING, April 18 (Xinhua) -- China's central bank on Wednesday injected funds into the banking system via open market operations to maintain liquidity.

The People's Bank of China (PBOC) conducted 150 billion yuan (about 23.9 billion U.S. dollars) of seven-day reverse repos, according to a PBOC statement.

A reverse repo is a process by which the central bank purchases securities from commercial banks through bidding, with an agreement to sell them back in the future.

The operation aims to offset factors such as tax payments, and maintain liquidity in the banking system at a reasonable and stable level, the statement said.

The interest rate for the reverse repos was unchanged at 2.55 percent.

In Tuesday's interbank market, the overnight Shanghai Interbank Offered Rate, which measures the cost at which banks lend to one another, rose 8.3 basis points to 2.665 percent.