Shenzhen Intermediate People's Court heard that Leung then fled the scene, leaving Li seriously injured on the road but dragging the stroller - which had become caught under his container truck with the baby still inside - for some distance.

The boy's body was found in the Tanglangshan tunnel four days later. Leung returned to Hong Kong within an hour of the accident.

The driver's mother fainted on hearing the sentence, saying she thought it too heavy. 'I hope someone can really help my son with heart,' she said, sobbing.

The baby's parents were also in court to hear the verdict. They said no matter how heavy the sentence, it could not bring back their son. 'He was only a small baby, he didn't even know how to talk when he was tortured. He just knew how to cry. It is really unbearable,' his father, Zhou Yigui, said. 'I really do not want to think about the accident again. If I think, I will be angry.'

Zhou said he would claim more than 300,000 yuan (HK$350,000) in compensation from the driver, who will do prison labour during the two-year suspension of the sentence.

Dong Wenge, a Shenzhen lawyer, said it was unlikely the death sentence would be carried out. If Leung behaved well, it would probably be commuted to 20 years to life in jail.

'This is a characteristic in China's legal system. Basically those criminals receiving such sentences do not need to die,' he said.

Leung had 10 days to lodge an appeal with a higher Guangdong court, he said.

Time to act

The number of days after his sentencing that truck driver Leung Koon-biu has to lodge an appeal with a higher court: 10