Chinese police pleaded with the public Wednesday for information about five newborn babies discovered in the back of a stolen car.

The three boys and two girls, all about 10 days old, were found in the backseat of a black four-door sedan when police stopped the car at a toll booth in north China's Hebei province on Sunday, said Zhang Lianying, the director of Nangong city's Highway Patrol.

Police have confirmed the car was stolen two weeks ago in Shanghai, 700 miles south of Nangong, Zhang said. But he said they have been unable to identify any of the babies.

The Beijing Youth Daily and several other papers published photos Wednesday of the five babies swaddled in blankets and lying close to each other on a bed with numbers above their heads.

The Youth Daily ran a banner headline above the pictures asking: "Does anyone know the Moms and Dads of these five babies?" It included the number of a hot line in Nangong to call.

China has a thriving trade in babies that are stolen or bought from poor families and then sold to couples who want another child, a servant or a future bride for a son.

The car caught the attention of a highway patrolman when its driver suddenly switched lanes while waiting to pay the toll.

When police tried to question the driver, he and another male in the passenger seat refused to get out or roll down their windows. A minute later, they suddenly jumped out brandishing knives and ran away, Zhang said. Police chased the men but failed to catch them, he said.

Zhang said that once police found the five babies in the backseat, they were immediately taken to a local hospital, where doctors said they were in good health and all about the same age.

Nangong is 150 miles southwest of Beijing.

Thousands of babies are also abandoned every year in China. Many are girls given up by couples who, bound by rules that limit most urban families to one child, want to try to have a son. Others are left at orphanages or by the roadside by unmarried mothers or poor families.