A woman found a two-year-old boy driving a battery-operated toy car down the street in South Carolina in the early hours of the morning.

The woman notified the police, who contacted social services and took the child to the sheriff’s office.

Three hours later, small tire tracks led authorities to his parents’ house, who said they had put him to bed the previous evening at 9pm.

The surprised parents said their son must have got up while they were sleeping, unlocked the door and driven away in his diaper and jogging trousers.

Major Allen Dailey of the Sumter County Sheriff’s office told Fox News that this kind of incident had happened before in the neighbourhood, but luckily the children had never been hurt.

He warned parents to lock their doors at night, and keep the lock or chain out of the child’s reach.

“If a small child like that gets out like that it could get hit by a car, or an animal or a dog could attack them and of course we don’t want that,” he said.

“We want our children to be safe.”

The parents will not face criminal charges after their adventurous two-year-old left the house without their permission.