Australian police accessed Chinese diplomats' emails and messages as part of foreign political interference investigation

Australian police accessed the communications of top Chinese diplomats and named a Chinese consular official in a warrant as part of an investigation into political interference, in the months before a crackdown on Australians in China.

Key points:

Correspondence between Chinese diplomats and a policy adviser to NSW Labor MP Shaoquett Moselmane has been seized by Australian police

The seizures were made as part of an investigation into an alleged plot to infiltrate the NSW Labor Party

The Consulate-General in Sydney says the accusations are "nothing but vicious slanders"

The ABC has uncovered explosive details of the highly sensitive investigation that has privately infuriated the Chinese Government in recent months as the Australia-China relationship has deteriorated into its worst crisis since the 1989 Tiananmen Square massacre.

Search warrants seen by the ABC reveal the Australian Federal Police (AFP) are investigating whether China's Sydney consulate conspired with a New South Wales MP's policy adviser, John Zhisen Zhang, in a plot to infiltrate the Labor Party and influence voters.

The warrants identify Sydney Consul Sun Yantao, who is responsible for managing relations with the Chinese diaspora and pro-Beijing organisations.

Mr Sun was appointed to the Sydney consulate by the Overseas Chinese Affairs Office, which has been taken over by China's foreign influence agency, the United Front Work Department (UFWD).

In a statement, the Consulate-General in Sydney said accusations it "engaged in infiltration activities are totally baseless and nothing but vicious slanders".

"The Chinese Consulate-General in Sydney is committed to promoting friendly exchanges and pragmatic cooperation in various fields between the Chinese side and New South Wales," the statement said.

"It always observes international law and basic norms of international relations while exercising duties in Australia."

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