Rural Chinese children increasingly risk being sold as their farmer parents flock to cities looking for work.

The government has cracked down harshly on such cases, and that the trend is decreasing.

In recent years, an estimated 150 million to 200 million people have moved from the Chinese countryside to urban areas, where their labor at factories and construction sites has fueled breakneck economic growth.

Several hundred million more are expected to leave China's vast rural hinterland in the next 15 to 20 years.

Children who are disabled or have with HIV/AIDS also face increased risk of being trafficked and are sometimes forced into panhandling.

It is estimated that tens of thousands of boys from western China's Xinjiang region have been bought or kidnapped by gangs, who force them into pickpocketing and other nonviolent crime in China's eastern cities.

Ethnic minority girls from Yunnan province and the Guangxi region in the south risk being forced into the sex trade in China and nearby Southeast Asian countries like Thailand and Malaysia.

Children left behind in villages are vulnerable because they are often looked after by grandparents _ who often need care themselves _ or by institutions that lose track of the children.

However, those who migrate with their parents are also in danger because they are thrust into unfamiliar surroundings with limited social services, and their parents are often busy working.

China currently defines child trafficking victims as children up to age 14 old who are sold or kidnapped.