Police found an abandoned car allegedly used to kidnap a baby boy from his home in western part of Sydney. The vehicle was discovered in Bargo with no sign of the abductor or the child.

The suspected kidnapper was the father of the eight-month-old boy, Zayden. The car, a Toyota Camry, was found by police along Avon Dam Road at around 6:50 am on July 26. The kidnapper's vehicle was discovered almost 12 hours after the suspect kidnapped the baby and his 16-year-old mother at knifepoint inside their home in Chester Hill.

Police have yet to confirm the reports of witnesses, saying the car used by the kidnapper had crashed into a tree. The vehicle was empty by the time the police arrived at the scene.

Authorities have urged the public to help find the suspect and his young son. Official police reports said the 24-year-old man had a knife when he forced his way inside a house on Kenthurst Place in Chester Hill around 8:30 pm on July 25. After using his knife to threaten the lives of the baby and his mother, the suspect was able to get them to come with him.

The suspect had tattoos on his chest and arms. Witnesses from the same neighborhood saw him drive away in a Toyota Camry.

Police said that around 10 pm on the night of the kidnapping, the car had stopped at a truck stop on the Hume Highway at Douglas Park. The man assaulted the teenage mother and left her by the side of the road while taking off with the baby.

Police said the kidnapper is between 165 and 175 centimetres tall. Aside from his tattoos on the arms and chest, he had brown hair, thin build and wore a blue jumper with green tracksuit pants.

Marco (no surname given), the baby's grandfather, appealed to the man through the media to return the baby boy safely and not do anything stupid.

The police, with a dog squad, have already set up a perimeter in Bargo and is currently searching the area for the kidnapper and the baby.

The police asks people who may have seen the man fitting the description and travelling with a child to call 000 immediately.