Seven survivors of the Nanjing Massacre have passed away this year, according to the Memorial Hall of the Victims in the Nanjing Massacre by Japanese Invaders.

People visit a photo exhibition on Nanjing Massacre survivors at the Memorial Hall of the Victims in Nanjing Massacre by Japanese Invaders, in Nanjing, East China's Jiangsu Province. (File photo: Xinhua)

Their deaths reduced the total number of registered survivors to 65, according to the memorial hall.

The Nanjing Massacre took place when Japanese troops captured the city on Dec. 13, 1937. Over six weeks, they killed close to 300,000 Chinese civilians and unarmed soldiers in one of the most barbaric episodes of World War II.

In 2014, China's top legislature designated Dec. 13 as the national memorial day for the victims of the Nanjing Massacre.

The Chinese government has preserved the survivors' testimony, recorded in both written documents and video footage. These records of the massacre were listed by UNESCO in the Memory of the World Register in 2015.