Stockholm - Somaly Mam of Cambodia who has campaigned against trafficking and child prostitution was Wednesday named winner of the World's Children's Prize.

Queen Silvia of Sweden, one of the patrons of the prize, was to present the award, worth 150,000 dollars, at a ceremony on Friday.

Somaly Mam was sold to a brothel as a young girl and has campaigned against trafficking for the past 12 years. She has set up three safe houses for girls rescued from brothels and offers them food, health care, schooling and job training, organizers said.

Her organization that is known under its French acronym AFISEP has helped some 3,000 former sex workers.

However, Somaly Mam's campaign against the sex trade in Cambodia has "earned her many enemies and death threats. Her own 14 year-old daughter was kidnapped, raped and sold to a brothel" two years ago, organizers said.

Somaly Mam was selected by a jury of former child soldiers, street children, bonded workers and refugees from 17 countries.

Josefina Condori of Peru who has highlighted the plight of girls who work as maids in her native country and Agnes Stevens of the United States who set up the group School on Wheels to help homeless children in the US received honorary awards.

Somaly Mam was also winner of the Global Friends' Award in a worldwide vote among some 6.6 million children.

Patrons of the World's Children's Prize include Queen Silvia, former South African President Nelson Mandela, East Timor President Xanana Gusmao, Carol Bellamy the former head of UNICEF, and Nobel economics prize laureate Joseph Stiglitz.

The award was established in 2000 by the Swedish non-governmental organization, Children's World.

In 2007, Zimbabwe child rights activist Betty Makoni won the World's Children's Prize and the World's Children's Prize for the Rights of the Child. (dpa)