Background: A look at China's Martyrs' Day

In August 2014, China's top legislature approved September 30 as Martyrs' Day.

It is estimated that China has about 20 million martyrs.

The decision aims at "publicizing martyrs' achievements and spirits, and cultivating patriotism, collectivism, and socialist moralities to consolidate the Chinese nation's cohesiveness," the top legislature said.

Martyrs' Day was set on the day before China's National Day on October 1. This is also the day when foundations were laid for the Monument to the People's Heroes in 1949, which stands at the southern end of Tian'anmen Square.