Members of Hong Kong's pro-democracy camp Emily Lau (2nd L), Yeung Sum (C) and Martin Lee (2nd R) take part in a demonstration on the streets of Hong Kong on May 31, 2009 in the run-up to the 20th anniversary of Beijing's crackdown on pro-democracy protesters in Tiananmen Square. Organisers said around 5,000 people rallied through the streets of the southern Chinese city to mark the anniversary of the military crackdown in 1989 which left hundreds, possibly thousands dead following weeks of protests in the capital. Meanwhile, Hong Kong police have charged two men over a plot to assassinate Martin Lee, one of the city's leading pro-democracy campaigners, police said on May 31.