Envoy's suicide raises tension between China and Japan

China and Japan are locked in a bitter war of words after the Japanese government accused spies from China of being responsible for the suicide of one of its diplomats.

The unnamed official, who was based in Japan's consulate in Shanghai and committed suicide in May last year, left a series of suicide notes claiming he was being blackmailed by a Chinese intelligence agent over his relationship with a hostess in a karaoke bar. The allegations, first voiced on Wednesday by the Japanese Foreign Ministry, were denounced by Beijing yesterday as "vile" and a "smear" on China.

The furore threatens to plunge Sino-Japanese relations to a new low. Chinese anger over Japan's failure to apologise for its actions during the Second World War, Japanese fears over China's increased military spending and a dispute over the ownership of islands rich in natural resources have exacerbated friction between Asia's two major powers.

Having dismissed reports in the Japanese press about the suicide as "groundless", Beijing was forced on to the defensive by Japan's claims. "This is completely out of ulterior motives and we express our strong indignation at the vile behaviour of the Japanese government, which deliberately smears China's image," China's Foreign Ministry spokesman, Qin Gang, said.

Tensions between China and Japan came close to breaking point last week after Japan's Foreign Minister Taro Aso accused China of posing a "considerable threat" to north-east Asia. He also claimed that China was spreading fear in the region by increasing spending on its military. Beijing described his remarks as "highly irresponsible".

According to Japanese reports, the diplomat was responsible for communications in the Shanghai consulate. The highly sensitive post involved encrypting classified information before it was sent to the Foreign Ministry in Tokyo. In one suicide note, the diplomat claimed his relationship with a karaoke bar hostess had led to him being pressured by a Chinese agent to reveal details of the flights used to carry classified documents to Tokyo and to pass on information about consulate staff.

"We believe people with the Chinese security authorities conducted regrettable actions," Japan's Foreign Ministry spokesman Yoshinori Katori said on Wednesday. He said the agent's actions violated the 1961 Vienna Convention on Diplomatic Relations and Japan had lodged four protests with Beijing but had yet to receive a satisfactory response.

In one note, the diplomat said that he could not countenance passing on secrets to China. "If I were to do more, I would have to sell Japan. I cannot sell my own country," he wrote.

Despite the fact that China and Japan are each other's biggest trading partners, their relationship has foundered in recent months. Chinese anger over Japan's failure to apologise for events such as the Rape of Nanjing, in which 300,000 Chinese civilians were slaughtered by the Japanese army in 1937, boiled over in April when thousands of Chinese were involved in violent protests against Japanese diplomatic missions and businesses. A poll by the Japanese Cabinet Office in October revealed just 32.4 per cent of respondents felt friendly towards China.