Chinese warship accused of endangering Australian Navy divers with sonar pulses

A Chinese warship has been accused of injuring a team of Australian Navy divers with sonar pulses in a tense confrontation that threatens to sour improving relations between the two countries.

The divers were from an Australian frigate that was forced to stop while sailing in international waters off the coast of Japan on Tuesday, due to tangled fishing nets around its propellers.

As they worked to clear the nets, a Chinese Navy destroyer approached at close range and began to operate its hull-mounted sonar.

The crew of Australia’s HMAS Toowoomba reiterated that a dive was underway - a message that had already been communicated via maritime channels - and asked the Chinese vessel to keep clear. But despite acknowledging the communications, the destroyer moved even closer.

“Medical assessments conducted after the divers exited the water identified they had sustained minor injuries, likely due to being subjected to the sonar pulses from the Chinese destroyer,” Australia’s Defence Minister Richard Marles said on Saturday.

He branded the Chinese action “unsafe and unprofessional conduct” and said Canberra had expressed “serious concerns” to the Chinese government.

HMAS Toowoomba had communicated that it was conducting a diving operation on maritime channels “at all times,” he added.

Sonar pulses are used to establish the position of underwater objects by emitting a signal that travels through the water and bounces off objects, but they can cause dizziness and hearing injuries if used around divers.

‘Not the act of a friend’

Australia’s opposition home affairs spokesman James Paterson described the Chinese vessel’s behaviour as “incredibly risky” and “frankly not the act of a friend.”

He urged Prime Minister Anthony Albanese to raise the matter with Chinese President Xi Jinping at this weekend’s APEC summit in San Francisco, which both leaders are attending.

The incident could mar improving relations between the two countries. Following Mr Albanese’s successful visit to Beijing earlier this month, China eased trade sanctions on Australian exports and signalled the possibility of more positive future ties.

Military analysts said the naval incident was inconsistent with the recent improvement in political and diplomatic links.

Dr Euan Graham, a senior analyst at the Australian Strategic Policy Institute, told the Sydney Morning Herald that a key question was whether China knew there were divers in the water. “If they did, it looks very bad indeed,” he said.

“Time and time again we see China resorting to so-called ‘grey zone’ activity [aggressive activity that falls short of armed conflict], but this is pretty black and white,” he added.

“It’s nowhere near the area China claims to own and designed to harass, intimidate and make it more difficult for Australia and Japan to work together.”

‘Very odd’

Neil James, executive director of the Australian Defence Association, said the incident was “very odd” in view of the success of Mr Albanese’s visit to China.

But he told the newspaper it demonstrated a pattern of “unnecessary and provocative behaviour.”

In 2019, Australian Navy helicopter pilots were targeted with laser beams as they flew over the South China Sea, in a series of attacks suspected to originate from the Chinese military. 

In 2022 a Chinese warship reportedly aimed a military-grade laser at an Australian air force plane while sailing through Australia’s exclusive economic zone.

In the same year, a Chinese spy ship was monitored off the West Australian coast, close to a top-secret naval communications base.

It is not known how many navy divers were affected in the latest incident.