BEIJING, July 1 (Reuters) - Activity in China's factory sector quickened to a six-month high in June, a government survey showed on Tuesday, adding to signs that the economy is regaining strength after an unsteady start to 2014.

China's official Purchasing Managers' Index rose to 51 in June from May's 50.8, the National Bureau of Statistics said.

Economists had expected the reading to rise to 51 in June.

(Reporting By Xiaoyi Shao and Kevin Yao; Editing by Kim Coghill)