A group concerned with the abduction of Japanese by North Korea blasted two senior members of the Liberal Democratic Party on Sunday for secretly making contact with Pyongyang officials.

At a meeting of its executives in Tokyo, the National Association for the Rescue of Japanese Kidnapped by North Korea said it will hold a major rally April 30 to call for economic sanctions against North Korea.

Participants in Sunday's meeting said the action taken by the two LDP members -- Taku Yamasaki and Katsuei Hirasawa -- went against the call by NARKN and a parliamentarians' group helping the abductees that Japan should only have intergovernmental talks with North Korea.

Yamasaki, former LDP vice president who lost his Diet seat in the November general election, and Hirasawa, an LDP lawmaker who is secretary general of the parliamentarians' group, made a two-day trip to China last week to hold talks with North Korean officials. Hirasawa has submitted his resignation from the post with the lawmakers' group.

On Sunday, Hirasawa said North Korean officials last year admitted to errors made in documents about the 10 Japanese abductees who have not returned to Japan.

Speaking before an audience in Kanazawa, Ishikawa Prefecture, Hirasawa, who also met Pyongyang officials in December, said they have acknowledged the errors, saying the documents were made in a hurry.

According to Hirasawa, the officials said they would like to provide an accurate account of the 10. He added, "Though some may have died, I am sure others are still alive."

Hirasawa has also told Kyodo News that North Korean officials said they can provide evidence that senior diplomat Hitoshi Tanaka promised to return the five repatriated abductees back to Pyongyang.