Children armed with bricks and logs could be seconds away from causing a fatal crash on a busy dual carriageway near Oxford.

In just three days, a car and a lorry passing underneath a flyover on the A40 at Wheatley were targeted by youths above.

Police believe in both cases the drivers were lucky to escape without serious injury.

During the first incident, a man was driving from the M40 junction 8a towards Oxford when he spotted a bundle of logs falling from the bridge above.

They missed his windscreen by inches and smashed into his car's bonnet.

Two days later, at the same spot, a brick was hurled from behind some bushes and smashed through a truck driver's windscreen.

Both drivers escaped unharmed but police today warned that next time someone could be seriously injured.

Pc Paul Gregory said: "We have had nothing so serious as this before. "Sometimes plastic bottles or paper has been thrown from the bridge on to the carriageway, but there has been nothing like this.

"They were both serious incidents and could have caused a serious - or possibly a fatal - accident."

The first attack happened at about 3.30pm on Wednesday, March 26, when a man and his passenger were driving towards Oxford.

The driver, from Oxford, managed to keep control of his car when the logs crashed onto his bonnet. He stopped at Forest Hill layby and alerted police.

His car bonnet was so badly dented it had to be replaced.

Pc Gregory added: "The driver saw pieces of wood coming down from the bridge above him and hit the bonnet of his car.

"These pieces of wood could have gone through the windscreen and injured the people inside the car or caused the driver to be so distracted he swerved and had a serious accident.

"He was very shaken up and luckily avoided a nasty accident, which could have been fatal."

On Friday, March 28, a lorry driver from Swindon passed by the same spot when he saw a brick being thrown from behind a row of bushes.

It smashed through the windscreen of his cabin, but he maintained control and pulled over at the same layby less than half a mile along the A40.

Police are now patrolling the bridge during the hours when children are going to and from schools.

Officers have not been able to find the brick or logs thrown at the vehicles.

Anyone with information about either incident is urged to call police on 08458 505505 or Crimestoppers on 0800 555111.