BEIJING, April 14 -- China's central bank continued its net cash injections via open market operations Friday, the second straight day after a 13-day halt.

The People's Bank of China (PBOC) conducted 90 billion yuan (about 13.1 billion U.S. dollars) of reverse repos, a process by which the central bank purchases securities from banks through bidding, with an agreement to sell them back in the future.

The injection saw a net 70 billion yuan pumped into the financial system, offset by 20 billion yuan in maturing reverse repos.

The operations included 60 billion yuan of 7-day reverse repo prices to yield 2.45 percent, 20 billion yuan of 14-day contracts with a yield of 2.6 percent, and 10 billion yuan of 28-day agreements with a yield of 2.75 percent.

The move followed a central bank liquidity injection Thursday, which included 83.9 billion yuan through pledged supplementary lending and 110 billion yuan through reverse repos.

The restarting of such operations came after 40 billion yuan of reverse repos and 217 billion yuan from the medium-term lending facility matured Thursday, adding liquidity strain in the market.

The central bank has steered clear of interest rate cuts and avoided tinkering with reserve requirement ratios over the past year. An expanded range of tools, such as reverse repos and lending facilities, are managing liquidity and supporting growth.

China's monetary policy in 2017 is set to be "prudent and neutral," keeping appropriate liquidity levels and avoiding large injections.