"China, which had been transparent about its civilian plutonium programme until recently, stopped annual voluntary declarations to the International Atomic Energy Agency on its stocks of civilian plutonium in 2017"

Not good.

Concerns grow over China nuclear reactors shrouded in mystery | Business and Economy News | Al Jazeera
https://www.aljazeera.com/economy/2021/5/19/concerns-grow-over-china-nuclear-reactors-shrouded-in-mystery