Chinese people living in North Korea are fretting over a recent espionage case in which the Chinese residents were referred to as primary informants of the South Korean spy agency, Radio Free Asia said Monday.

Citing anonymous sources, the report said Chinese nationals in North Korea and North Korean merchants who frequently visit China are worried about the case’s potential backlash.

The two South Korean citizens arrested and detained by North Korean authorities confessed to hiring Chinese nationals as informants in a press conference held by North Korean authorities last week.

Chinese nationals, including ethnic Korean-Chinese can enter and leave