The Japanese government is seeking an increased ban on senior members of a Tokyo-based pro-Pyongyang association of ethnic Koreans from reentering Japan.

Japan’s Kyodo News quoted a Japanese government official as saying Wednesday that Tokyo is considering expanding the scope of related regulations so that some 20 high-level members of the pro-Pyongyang “Chongryeon” will not be allowed to reenter Japan. The official said that such a measure is aimed at blocking Chongryeon members from contacting North Korean officials.

So far, the Japanese government has banned six senior members of the pro-Pyongyang group from reentering Japan due to their alleged involvement in the North’s abduction of Japanese nationals.