China test fired an long-range ballistic missile with a dummy warhead in the Pacific Ocean on Monday, the first such launch in two years.

The missile was launched from a Chinese nuclear-powered submarine and sent a “mock warhead” into the Pacific Ocean, according to a report from Xinhua, China’s official news agency.

“The missile landed accurately in the designated area,” the report said. The test launch at 12:01 p.m. Beijing time, Xinhua said, was “not directed against any specific country or target.”

It was not immediately clear where the missile landed. The launch came as the leaders of Australia and Fiji announced a mutual defense treaty and a regional security alliance, the latest in a string of agreements Canberra has been striking with Pacific Island nations widely viewed as efforts to push back against China’s encroachment in the region.

Governments in the region were warned of the launch shortly beforehand.

The previous test in September 2024, when China fired an intercontinental ballistic missile carrying a dummy warhead across the Pacific Ocean into waters near French Polynesia, drew alarm from countries in the region. It marked the first time in more than four decades that China had publicly announced testing an ICBM in the Pacific region.

Winston Peters, New Zealand’s foreign minister, said in a statement the country was “deeply concerned” and that the test seemed to be part of “a recurring pattern by China.”

“New Zealand considers this an unwelcome and concerning development. We, like our neighbors in other Pacific countries, have no interest in China using the South Pacific as a testing site for missile capability,” he said.

Australia’s foreign minister, Penny Wong, called the test “destabilizing to the region” and said that it was “in the context of a rapid military buildup by China, which is lacking in the transparency and reassurance as to intent that the region expects.”

The Japanese government said in a statement on Monday that it had “conveyed its serious concern regarding the intensification of China’s military activities.” Japan had urged China to reconsider the launch, the statement said.

In its announcement on Monday, the Chinese government did not specify the type of missile it tested.

Jeffrey Lewis, a scholar at Middlebury College in Vermont who studies China’s nuclear weapons modernization, said that he thought the Chinese military was most likely testing the JL-3, a new generation ICBM that is designed to be launched from submarines.

China displayed the JL-3 missile at a military parade in Beijing last year, part of its growing array of nuclear weapons.

The latest test suggested that China’s test launches of nuclear-capable weapons will accelerate in coming years, said Mr. Lewis.

“It suggests a new era of testing where every system will get its moment in the sun,” he said, referring to China’s growing array of new nuclear-capable missiles.

“The Chinese have historically tested their ICBMs less than other countries,” Mr. Lewis said, referring to intercontinental ballistic missiles. “I think that was political and now those politics have changed and I think they’re adopting an approach of testing more. They’re willing to pay the political costs of that in a way that they weren’t in the past.”

The 2024 test most likely involved a DF-31 road-mobile missile that was launched from Hainan, an island province in southern China, according to an analysis published by the Federation of American Scientists.

Laura Chung and Javier C. Hernández contributed reporting.