Australia learned about Chinese live-fire naval drills off the country’s coast that forced dozens of flights to be diverted via an alert from a commercial pilot, authorities said on Monday.

China’s Defense Ministry says that Australia made “unreasonable accusations” and deliberately hyped the situation after three planes headed to New Zealand changed course in midflight because of live-fire drills by the Chinese navy.

New Zealand raised fresh concerns Monday over nearby live-fire drills conducted by Chinese warships armed with “extremely capable” weapons, an unprecedented show of firepower last week that analysts say are part of Beijing’s ongoing plan to build a blue-water navy with global reach.

Australia's top military commander says an undetected nuclear submarine could not be ruled out as part of the Chinese flotilla.

Australia's Foreign Minister Penny Wong raised concerns with her Chinese counterpart on Friday over inadequate notice given by the Chinese navy of a rare live-fire exercise in international waters between Australia and New Zealand that forced airlines to divert flights.

Airlines have been contacted by Australia’s air traffic control agency warning them of reports of live fire off the country’s east coast where a Chinese navy task group has been operating, the agency and Australian officials said.

Air officials first found out about Chinese live-fire drills from a Virgin pilot, an inquiry has heard, as Beijing ships continue to lurk off Australia's coast.