A court in southern Vietnam jailed six child traffickers for up to 12 years for smuggling babies to neighbouring China, but the two ringleaders remain at large, a court clerk said Friday.

Nguyen Thi Sang, 41, from Ho Chi Minh City and Pham Thi Thoa, 30, from the northern port city of Haiphong were each sentenced to 12 years' jail in Thursday's trial, a court clerk told AFP.

The traffickers had bought at least two infants when the children were just a few months old from a maternity hospital in Ho Chi Minh City, formerly known as Saigon, for about five million dong (300 dollars) each.

They successfully trafficked the two babies to the northern town of Mong Cai bordering China to sell them to Chinese buyers before they were arrested by police last December.

Four other ring members were handed sentences of between three and seven years but the two alleged leaders of the network, Duong Thi Mui and her sister Duong Tu Anh, were still being hunted by police.