China may have secretly set off low-level underground nuclear test explosions despite claiming to observe an international pact banning such blasts, the U.S. State Department said in a report on Wednesday that could fuel U.S.-Chinese tensions.
The finding, first reported by the Wall Street Journal, may worsen ties already strained by U.S. charges that the global COVID-19 pandemic resulted from Beijing's mishandling of a 2019 outbreak of the coronavirus in the city of Wuhan.
U.S. concerns about Beijing's possible breaches of a "zero yield" standard for test blasts have been prompted by activities at China's Lop Nur nuclear test site throughout 2019, the State Department report said.