Australian Prime Minister Scott Morrison says allegations of a plot to plant a Chinese spy in Canberra's parliament are "deeply disturbing".
The allegations - first aired by local network Nine - assert that a suspected Chinese espionage ring approached a Chinese-Australian man to run as an MP.
In a rare public statement, the nation's domestic spy agency has confirmed it is investigating the allegations and taking them seriously.
China is yet to respond to the claims.
Mr Morrison said he found the reports troubling but warned against "leaping to conclusions".
What are the allegations?
On Sunday, Nine's 60 Minutes programme reported that suspected Chinese agents approached a luxury car dealer, Nick Zhao, ahead of Australia's general election - which took place in May.
They allegedly offered him A$1m (£520,000; $680,000) to fund his run for a Melbourne seat as a candidate for the ruling Liberal Party, of which Mr Zhao was already a member.
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Mr Zhao gave information about the alleged approach to the Australian Security Intelligence Organisation (Asio) last year, Nine reported.
He was found dead in a hotel room in Melbourne in March. His death has prompted a coroner's inquiry.
What other claims have been made?
Nine has also reported that a man claiming to be a Chinese spy has applied for asylum in Australia, in an unrelated case.
Wang "William" Liqiang has reportedly given authorities information about operations in Hong Kong, Taiwan and Australia, saying he was "personally involved" in espionage work.