China's exports to North Korea rose at a slower pace in September, but shipments of masks and other COVID-related items surged as the isolated country stepped up its battle against possible COVID-19 flare-ups, Chinese customs data showed on Monday.

Pyongyang declared victory over COVID in August, while its news agency and state television showed elderly people and university students wearing masks in October, with public health experts advising people to don facial protection to guard against the possible resurgence of the virus.

North Korea has not confirmed how many people have caught COVID, apparently because it lacks the means to conduct widespread testing.

China exported 10.56 million masks to North Korea in September compared with just 210 in August, according to data released by Chinese customs. Some 40,000 pairs of rubber gloves were shipped to North Korea in September, versus none in August.

Pyongyang bought two million thermometers last month, worth $280,000, after no purchases in July and August.

China's overall exports to North Korea rose 62.5% year-on-year to $90.07 million, after leaping 217.7% in August.

Top exports by value were rubber tires, wigs, soybean oil and tobacco.

China said in late September that cross-border freight train operations between North Korea and China had resumed, ending a five-month suspension to limit the spread of COVID-19. (Reporting by Liangping Gao and Ryan Woo; Editing by Mark Potter)