A top aide to Japan’s Prime Minister Shinzo Abe may have secretly met North Korean officials in the Chinese port city of Dalian near North Korea in late October, Kyodo News reported.

The February 10 report, which cited unnamed diplomatic sources in China, said that Isao Iijima, a special adviser to Abe’s cabinet and a former secretary to former Prime Minister Junichiro Koizumi, secretly visited Dalian for about four days in late October and possibly met North Korean officials there.

The report on Iijima’s visit comes after senior Japanese diplomats were found to have traveled to Vietnam in late January