Defense Minister Richard Marles said HMAS Toowoomba – a long-range frigate – was conducting a diving operation in Japan’s exclusive economic zone on November 14 to remove fishing nets from its propellers when the incident occurred.

“While diving operations were underway, a PLA destroyer (DDG-139) was operating in the vicinity and closed toward the ship HMAS Toowoomba,” Marles said in a statement, referring to a PLA Navy ship.

He said that although the Australian ship notified the Chinese warship of the diving operation and asked it to remain clear, the destroyer approached “at a closer distance.”

“Shortly after, it was discovered that the sonar mounted on the ship’s hull was operating in a way that posed a safety risk to the Australian divers who had to get out of the water.”

Marles said the behavior was “unsafe and unprofessional.”

What do five-nation military exercises say about US strategy in the Indo-Pacific region?

The Chinese embassy in Australia did not immediately respond to a request for comment.

The Defense Minister said medical assessments found minor injuries to the divers likely caused by the destroyer’s sonar pulses.

“Australia expects all countries, including China, to operate their militaries in a professional and safe manner,” Marles said, adding that the safety and well-being of Australian military personnel is the government’s “top priority.”

The Diving Medical Advisory Committee, an independent organization based in London, has warned that sonar sound waves can cause dizziness, hearing damage and organ damage to divers.

The Australian Navy previously said the Australian ship was in the waters as part of Operation Argos, to enforce sanctions on North Korea during a regional deployment.

01:46

A Chinese fighter plane almost collides with a US military plane over the South China Sea

A Chinese fighter plane almost collides with a US military plane over the South China Sea

China has emerged in recent years as an increasingly assertive power in the Indo-Pacific region, including improving security relations with the Solomon Islands in July.

Earlier this year, Australia – a close US ally – held two weeks of war games involving more than 30,000 troops with the US in a show of force amid China’s growing regional influence.

It was positive. We talked [about] Albanese told reporters that Premier Lee will come to Australia next year after the recent meetings resume.

Albanese said he also asked Xi to remove remaining trade restrictions on Australian products.

China is Australia’s largest trading partner, but relations declined in 2020 when Beijing exerted significant economic pressure, in what was seen as the rising Asian power sending a warning to other Western countries.

Australia’s then-conservative government, in line with US positions, barred Chinese tech giant Huawei from 5G contracts and called for an investigation into the origins of Covid-19, which was first detected in China.

China responded by imposing punitive tariffs on a variety of Australian goods including coal, barley and wine.

China has reversed course and removed most restrictions since Albany, of the Labor Party, took office in May last year.

Additional reporting by AFP