Photo/Illutration Flowers and prayers are offered in Tokyo’s Chiyoda Ward on Aug. 23 for the tens of thousands of Japanese war detainees who died in Siberian internment camps after World War II. (Reina Kitamura)

A memorial service for Japanese war detainees who died in Soviet-run internment camps in Siberia after World War II was held at Tokyo's Chidorigafuchi National Cemetery on Aug. 23.

This year for the first time, relatives were due to read aloud the names of the 46,300 Japanese who perished, starting from early evening.

This year also marks the 18th time the annual event has been hosted by a support organization for victims and survivors of the camps.

Soviet leader Joseph Stalin on Aug. 23, 1945, ordered Japanese captives to be interned in Siberia, where conditions were extremely harsh. Japan surrendered in World War II on Aug. 15 of that year.

Tsuneo Murayama, a survivor who died at the age of 88 in 2014, created the list of names of the victims after he was released and returned to his hometown in Niigata Prefecture following four years as a detainee from 1945 in Khabarovsk. It took him more than 10 years to complete the list.

Records of detainees handed over to the Japanese government by the Soviet Union were not always accurate.

Murayama worked diligently to identify each victim’s full name and published the list in 2007, paying for it out of his own pocket.

The memorial organizer estimated it will take around 46 hours for the 30 to 40 survivors and relatives of the victims to take turns reading out all names using Zoom. The service will also be covered on YouTube.