A Chinese court has passed a life sentence on the ringleader in a baby trafficking ring that bought and sold 43 infants, state media reported Tuesday.

Ren Suyan was sentenced by an Inner Mongolian court Monday for leading a gang that bought babies for between 500 and 9,700 yuan (62 and 1,200 dollars) and sold them for between 2,200 and 14,800 yuan, Xinhua news agency said.

The gang made over 200,0000 yuan between 1998 and 2004 for selling babies as young as two hours old, the report said.

Fifteen other gang members were jailed for between three and 13 years.

Ren and her husband were caught by police in May when they returned to Inner Mongolia after trying to sell a baby girl in Beijing, Xinhua said.

China's "one child" birth control policy, coupled with the country's long tradition of favoring boys, are seen as encouraging the trafficking of children.

Last year 3,500 children were rescued from their captors in 1,975 cases, earlier state media reports said.