China's inflation stepped up in September, with prices rising more than expected for both consumers and producers in a surprising signal of economic strength.

    Consumer prices rose 1.9 percent on-year in September, while producer prices surprised by rising 0.1 percent on-year, the first increase since 2012.

    The consumer price index (CPI) had been expected to rise 1.6 percent on-year and the producer price index (PPI) was expected to slip 0.3 percent, according to forecasts from a Reuters poll of economists.