NANJING - Xiong Shulan, a survivor of the Nanjing Massacre in east China, passed away at the age of 94 on Saturday, reducing the number of living registered survivors to 25, the Memorial Hall of the Victims in Nanjing Massacre by Japanese Invaders said on Monday.

The Nanjing Massacre refers to a period of history that started when Japanese troops captured the then Chinese capital on Dec 13, 1937. In the space of six weeks, the Japanese invaders killed approximately 300,000 Chinese civilians and unarmed soldiers in one of the most barbaric episodes of World War II.

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In 1937, after the Japanese forces entered Nanjing, Xiong survived by shaving her head and disguising herself as a boy.

Xiong was a veteran member of the Communist Party of China and had a passion for performing kuaiban, a traditional Chinese rhythmic storytelling art form.

Seven survivors, including Xiong, have passed away since the beginning of this year, as the number of those able to share firsthand accounts of the massacre continues to decline.

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

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