A priest who helped North Korean defectors flee their oppressive country was found dead in north east China near the border on Saturday.
Human rights activists have suggested that Pyongyang's security services played a role in his death.
Han Choong-ryul was from Korea and had Chinese citizenship. He was a priest at Changbai Church and was known to support defectors once they had reached China.
The Korea Herald reported that Choi Sung-yong, an activist, said it is likely Han was killed by three North Korean agents dispatched to the Jilin province of China just before the incident.
"The agents are known to have returned to their country," Choi said. "The priest had long supported North Korea defectors. North Korea seems to judge that his church is being used as a hideout for such North Koreans."
Han's mobile phone is reportedly missing, according to the Telegraph, which has potentially placed defectors and those who have aided them in danger.
North Korean defectors that are caught in China are sent back by authorities to the country, so there are leagues of people co-ordinating safe houses for use until they can cross the border out of China.
North Korean agents are known to cross the border to capture defectors.
"We have reports of this sort of thing happening before and we have seen a sharp increase in the security on the border with China since Kim Jong-un came to power," said Robert Park, a former prisoner of North Korea and founding member of the Worldwide Coalition to Stop Genocide.
"American and South Korean citizens doing this sort of work in north-east China might be a little safer, but Chinese citizens are in danger because their own government does nothing to protect them," he added.