Australia's authorities are investigating a Chinese national over a suspected espionage case at the country's top scientific organisation.

The man is suspected of unauthorised use of computers a highly-sensitive nanotechnology laboratory in Melbourne.

The laboratory works closely with Australia's Defence Science and Technology Organisation.

Australian intelligence chiefs have recently warned of the growing threats of industrial espionage.

The investigation by police and security agencies reportedly focuses on a post-doctoral student who until recently worked at the Commonwealth Science and Industrial Research Organisation (CSIRO).

"CSIRO became aware of a matter involving an employee suspected of unauthorised use of CSIRO computers," the laboratory said.

"We consider this a very serious matter," it added, without giving any further details.

The Sydney Morning Herald reported that the investigation was trying to establish whether the unnamed Chinese national had sent sensitive information to a foreign power.

The case may further test Canberra's relations with Beijing following a recent row over China's new air defence zone in disputed international waters, the BBC's Phil Mercer in Sydney reports.

Last week, Australia called in the Chinese ambassador over Beijing's unilateral decision.