Beijing vehemently denies the accusations, saying its policies in Xinjiang have eradicated extremism and boosted development.

Those denials have not stopped the United States from placing curbs on trade from the northwest region, and in January Washington banned imports from dozens more China-based companies over alleged ties to forced labour.

However, Chinese customs data released Thursday showed exports from Xinjiang to the United States rose 273.4 percent on-year to $2.5 billion during the period from January to August.

It was not immediately clear what the increase was due to.

Rights groups allege that China has detained more than a million Muslims, mostly Uyghurs, in a network of facilities in Xinjiang that are rife with violence, torture, forced labour, political indoctrination and other abuses.

Beijing says the facilities were voluntarily attended training centres that closed years ago after attendees "graduated".

The United States keeps a Uyghur Forced Labor Prevention Act entity list, which now numbers almost 150 as of January.

Goods wholly or partially made by firms on the list are restricted from entering the United States.

Overall exports to the United States -- China's largest single-country trading partner -- continued to fall in August, data showed earlier this month, sinking 11.8 percent from the previous month and 33.1 percent from a year earlier.

Trade tensions between Beijing and Washington have been on a rollercoaster ride in 2025, with both sides slapping escalating tariffs on each other.