People march to mark the fifth anniversary of Chea Vichea death in Phnom Penh; Vichea was shot dead at a news stand in central Phnom Penh in January

People hold a portrait of Chea Vichea, former president of the Free Trade Union of the Workers of Cambodia, and flowers as they march to mark the fifth anniversary of his death in Phnom Penh January 22, 2009. Vichea was shot dead at a news stand in central Phnom Penh in January 2004.REUTERS/Chor Sokunthea (CAMBODIA)

A woman burns incense and prays in front of a portrait of Chea Vichea, former president of the Free Trade Union of the Workers of Cambodia, to mark the fifth anniversary of his death in Phnom Penh January 22, 2009. Vichea was shot dead at a news stand in central Phnom Penh in January 2004.REUTERS/Chor Sokunthea (CAMBODIA)

A woman burns incense and prays in front of a portrait of Chea Vichea, former president of the Free Trade Union of the Workers of Cambodia, to mark the fifth anniversary of his death in Phnom Penh January 22, 2009. Vichea was shot dead at a news stand in central Phnom Penh in January 2004.REUTERS/Chor Sokunthea (CAMBODIA)