**China has formally arrested and charged four employees of mining firm Rio Tinto with stealing trade secrets and taking bribes, Chinese state media reports.**The accused are Australian national Stern Hu and three Chinese employees of the Anglo-Australian company.
They are charged with using “improper means” to obtain “commercial secrets” about China’s steel and iron industry, Xinhua reports.
The four have been in police custody in Shanghai since early July.
Rio Tinto denies any wrongdoing.
Australia has repeatedly sought a quick resolution of the case, but China has told Canberra not to interfere in the legal process.
China’s State Secrets Bureau on Monday accused Rio Tinto of spying on Chinese steel mills for six years and helping to inflate iron ore prices.
It said Chinese steelmakers had lost 700bn yuan ($102bn; £61.2bn) through overpaying for imported iron ore.