China's factory activity extended solid growth in September, twin surveys showed, as the nation's crucial exports engine revved up on improving overseas demand and underlined a steady economic recovery from the coronavirus shock.

The official manufacturing Purchasing Manager's Index (PMI) rose to 51.5 in September from 51.0 in August, according to data from the National Bureau of Statistics (NBS) on Wednesday, remaining above the 50-point mark that separates growth from contraction for the seventh month.

Analysts had expected it to pick up slightly to 51.2.