By Kang Seung-woo

Several North Korean agents were caught by Chinese police in March after attempting to kidnap a South Korean missionary at the Yanbian Korean Autonomous Prefecture, according to a media report.

"Five to eight agents of North Korea's Reconnaissance General Bureau (RGB) were detained in Jilin Province for trying to abduct a South Korean pastor," the Donga Ilbo reported, citing a source familiar with the incident.

The newspaper said the North's State Security Department (SSD) and the RGB are "competing" to abduct South Koreans helping North Korean refugees in China to show their allegiance to their young leader Kim Jong-un.

"Their rivalry has become stronger since last year and the latest kidnapping case seems to have been directed by RGB director Gen. Kim Yong-chol," it said.

Since 2013, Pyongyang has kidnapped South Koreans, with three now being held there.

Missionary Kim Jong-uk has been detained since October, 2013, while the North also arrested missionaries Kim Guk-gi and Choi Choon-gil for allegedly spying on the North in March.

In response to the report, the Ministry of Unification said that the government is confirming the case.

There is speculation that the kidnapping may evolve into a diplomatic conflict between China and North Korea.

"Although the North has denied that the agents existed, the case has already been reported to the Chinese leadership," the report said.

Beijing had turned a blind eye to North Korean agents' activities inside China before, but the arrest means it will not sit back from now on and let them do as they please.

In the wake of the execution of the North Korean leader's pro-China uncle, Jang Song-thaek, as well as its third nuclear test, both of which took place in 2013, the two sides have had strained relations.

Chinese President Xi Jinping has yet to meet with the North Korean leader since he took office in November 2012.