 Japanese archaeologists Torrii Ryuzo and Imanishi Ryu, in particular, were instrumental in the tomb excavations and in identifying the Nakrang Earthen Castle in Tosong-ri as the seat of the commandery.Over 1,500 tombs in all have been located, with sixty-three alone located in just one district (Chongbaek-dong).However, North Korea claims that all tombs are in fact of the Koguryo period, as it denies the existence of the Chinese settlement of Lelang, claiming it was a Koguryo city-state, and that the thousands of Chinese artifacts merely represent the burgeoning trade that the State of Nakrang had with the Han.