A U.S. official focusing on arms control has provided what he called new, declassified details of a Chinese underground ...

US intelligence agencies believe that China is developing a new generation of nuclear weapons and has conducted at least one covert explosive test in recent years as part of a broader push to ...

The allegations were leveled by U.S. officials late last week. Arms control experts worry that norms against nuclear testing are unraveling.

The U.S. government revealed new intelligence on Tuesday suggesting China may have conducted an ...

Remarks by a top administration official appeared to be aimed at dispelling skepticism of its assertions, as President Donald ...

A Trump administration official said that a remote seismic station in Kazakhstan measured an “explosion” in western China on ...

WASHINGTON — The United States is ready to carry out low-yield nuclear tests to match alleged secret explosions by China and ...

Officials have ruled out earthquakes or mining as the source of a 2.75-magnitude event in 2020 near China's nuclear test site.

CHINA has been accused of a massive nuclear expansion as well as carrying out secret tests, as the United States bids to ...

Scientific knowledge about the damaging effects of nuclear-weapons testing helped to end such tests. Those findings haven’t changed.

WASHINGTON — Democratic senators representing states that bore the brunt of the fallout from explosive nuclear weapons testing are seeking to pass legislation that would bar President Donald Trump ...