COVID cases have surged in the last week in the largest Chinese city on the border with North Korea, according to government health authorities, posing a threat to a cross-border rail trade route that the two sides reopened in September.

NK Pro analysis of Planet Labs satellite imagery shows trains continued to enter North Korea’s large freight disinfection and quarantine complex on the border through Nov. 26, around 10 days after cases spiked dramatically in China’s Liaoning Province.

However, numbers began to rise in the border city of Dandong — situated right up against North Korea