Activists ask people to wear black on 24th anniversary of Tiananmen crackdown

June 3, 2013 - A woman reads a book in front of portraits of victims of the crackdown of the June 4, 1989 pro-democracy movement in Beijing's Tiananmen Square at the June 4 Memorial Museum, run by pro-democracy activists at City University in Hong Kong. (AP)

June 3, 2013 - A Chinese policeman reacts as visitors to Tianamen Square wait for security screening near a sign which reads "Exit Square" on the eve of the 24th anniversary of the bloody military crackdown on protesters in Beijing. (AP)

Activists in China are calling on people to wear black on the anniversary of the bloody military crackdown on protesters in Tiananmen Square.

Beijing-based rights activist Hu Jia said he had been appealing for people to wear black T-shirts on Tuesday or light a candle at home on Monday evening to remember the event.

The Chinese government has never fully disclosed what happened and it remains a taboo topic inside the country. Hundreds, possibly more, were killed.

Hu said he felt the security around this year's event — the first since Xi Jinping became leader — was unprecedented.