Chinese police have concluded investigations into four employees of Australian mining giant Rio Tinto Ltd, who were suspected of infringing trade secrets and bribery.

The four were handed over to local procuratorate for prosecution, Shanghai public security authorities said Monday.

The four suspects included head of Rio Tinto's Shanghai office, Australian citizen Stern Hu, and three local employees Liu Caikui, Ge Minqiang and Wang Yong, said a statement by Shanghai Municipal Public Security Bureau.