A visitor is pictured at the Memorial Hall of the Victims in Nanjing Massacre by Japanese Invaders in Nanjing, east China's Jiangsu Province, Sept. 18, 2023. (Xinhua/Li Bo)

"Eternal Memory: The Nanjing Massacre Documentary Exhibition" opened on Wednesday at the Memorial Hall of the Victims in Nanjing Massacre by Japanese Invaders in Nanjing, East China's Jiangsu Province. Over 500 pieces of historical materials are on display, with some being publicly unveiled for the first time, according to the Xinhua News Agency.

The exhibition showcases over 500 documentary artifacts and more than 60 photographs, highlighting the major achievements in the collection, research, and international dissemination of Nanjing Massacre historical materials since the National Memorial Day for Victims was established.

The display features rare materials collected from countries and regions including the US, the UK, Germany, Japan, and Canada. These include archives, diaries, letters, audio-visual recordings.

Many of the documents are being shown publicly for the first time including the wartime diary of a Japanese soldier from the 13th Division and registries of victims, survivors, and eyewitnesses of the Nanjing Massacre.

The exhibition is organized around three themes: documentary preservation, research, and dissemination.

One part of the exhibition features over 300 archival documents from victims, perpetrators, and third parties, including survivor testimonies, diaries from Chinese and foreign nationals in Nanjing during the massacre, and confessions and news reports from perpetrators.

Another part presents more than 170 works authored or compiled by Chinese and foreign scholars, including research monographs, essay collections, and think tank reports.

The Nanjing Massacre took place when Japanese troops invaded then-Chinese capital on December 13, 1937. In over six weeks, approximately 300,000 Chinese civilians and unarmed soldiers were killed in one of World War II's most brutal episodes, according to Xinhua in a previous report.

In 2014, China's top legislature designated December 13 as the National Memorial Day for the victims of the atrocities. By the 2024 National Memorial Day, only 32 registered survivors remain alive.