The headquarters of the pro-Pyongyang association of Korean residents in Japan, or Chongryon, was auctioned off to a mysterious Mongolian company on Thursday.
The building in Tokyo was sold to AVAR for around US$51 million. Although the company is based in Mongolia, its owner and the purpose of the acquisition remain a mystery, according to Japanese broadcaster NHK.
Further stoking suspicions about the company is the fact that no Mongolian business has ever bought a building in Tokyo before.
Chongryon has effectively represented the North Korean government in Japan for decades, since Tokyo and Pyongyang do not have diplomatic ties.
Located in the Chiyoda district, the building stands 10 storeys high and has two basement floors. It was built in 1986 and put up for auction last year after a credit union run by Chongryon went bankrupt.
In the first round of the auction in March, a Japanese religious group with close ties to high-ranking North Korean officials won the bid for around $46 million but failed to secure the necessary funds.