“An Anzac-class frigate of the Royal Australian Navy stopped to conduct diving operations (to clear fishing nets that had fouled its propellors) in international waters off Japan when it was approached by a destroyer of the People’s Liberation Army Navy (PLAN).
The Australian ship, HMAS Toowoomba, then called PLAN ship Ningbo to inform them that they had divers down and asked them to keep their distance. So far so normal.
In response to this, it appears the PLAN destroyer closed the Toowoomba and turned on her bow-mounted sonar, putting enough sound energy into the water to injure the Aussie divers. A spokesperson for the Australian Defence Minister said, “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.””