Five children have suffocated in a village in eastern Pakistan after locking themselves in a parked car.

A family was taking an afternoon nap in their house in Wahndu village about 65 kilometres north of Lahore when its five children - aged between two- and six-years-old - sneaked into their uncle's car and locked themselves in.

Local police chief Samiullah Khan says the children were found unconscious after the family sent a teenaged boy to look for them.

"The children were pronounced dead at the hospital," he said.

"They died of suffocation as they could not unlock the car or slide down the windows."

Parents have told the police that it was an accident and there will be no further investigation.

- AFP