Efforts to confirm the number of South Korean casualties following last week’s earthquake in Japan are expected to be prolonged.

A Foreign Ministry official said Tuesday that Japan’s Self-Defense Forces are restricting access to areas that have been hit the hardest by the quake, including the prefectures of Miyagi and Iwate, as they are conducting search and rescue operations.

Contact with some 70 South Koreans in those regions has been cut off due to the quake and ensuing tsunami. As a result, the official said the process of confirming the safety of South Koreans is expected to take some time.

The official said Seoul has requested four northeastern regions in Japan to immediately notify the South Korean government the moment they confirm any South Korean deaths.

Earlier on Monday, the Foreign Ministry confirmed that the body of a 40-year-old South Korean national identified by his surname Lee was found at a construction site at a power plant in Ibaraki Prefecture. The ministry added that the body of a 43-year-old Japanese person of Korean descent was also found at the same site where Lee’s body was found.