Guan Shunhua, a survivor of the Nanjing Massacre, passed away on Wednesday at the age of 101, according to the Memorial Hall of the Victims of the Nanjing Massacre by Japanese Invaders in east China's Jiangsu Province. Her passing leaves only 21 registered survivors of the atrocity still living.

Guan was just a child when Japanese troops captured Nanjing, China's capital at the time, on December 13, 1937. In the space of six weeks, the Japanese invaders slaughtered approximately 300,000 Chinese civilians and unarmed soldiers in one of the most barbaric episodes of World War II. Guan survived but her uncle was cruelly cut down. 

Multiple registered survivors have passed away in recent years, meaning the number of those able to share firsthand accounts of the massacre is dwindling.

In 2014, China's top legislature designated December 13 as the National Memorial Day for Nanjing Massacre Victims. The Chinese government has preserved survivors' testimonies in both written and video archives – records that were inscribed on UNESCO's Memory of the World Register in 2015.

(With input from Xinhua)