China says it has rescued 23 children from trafficking gangs and detained 12 suspects in its latest effort to combat child abduction. Trafficking in children is a big problem in China. A traditional preference for male heirs and a one-child policy have driven a thriving market in baby boys. Abducted girls are often used as laborers or as brides for unwed sons. The official Xinhua News Agency reported Thursday that police in eastern Shanxi province had cracked 17 child abduction cases across the country. It says police began an investigation in November when several children were reported abducted. Xinhua says a preliminary investigation shows that three gangs were involved in the trafficking.