China’s detention of Rio Tinto executive Stern Hu has been extended, a source from the Australian Department of Foreign Affairs told AFP on Saturday. The unnamed spokeswoman said that China had confirmed that Hu would be detained for longer, but that the details of the case against him remained unknown. "Full details of the actual charges are not likely to be known until he is brought to trial," she said. Hu, an Australian citizen, was arrested on espionage charges in July. Meanwhile Australia’s prime minister Kevin Rudd told reporters in Thailand that he had held a meeting with Chinese prime minister Wen Jiabao about the case. Rudd declined to reveal the outcome of the meeting but said that the arrest and detention of Hu remains an "intense" issue in Sino-Australian relations.