A GANG of youths launched an object from a footbridge onto a speeding car below.

At about 3.30pm on Tuesday a 40 year-old man was driving between junctions 5 and 6 of the M4.

He spotted a group of two or three young people, possibly teenagers, resting what was later discovered to be a 5kg bag of rock salt on the railings of a bridge.

One of the group pushed the bag over, sending it plummeting down onto the victim’s car and smashing its windshield.

Miraculously uninjured, the man pulled over onto the hard shoulder.

No arrests have yet been made, and investigating officer PC Callum Brown, of the Joint Operations Unit for Roads Policing, is appealing for witnesses.

Slough Observer:

He said: “This reckless and stupid act could have had extremely serious consequences, and it is very fortunate that the driver of the vehicle which was hit was uninjured and was able to safely pull over to the hard shoulder.

“I would like to hear from anyone who was driving on the motorway at the time and saw a group of two or three teenagers on bicycles on or near the footbridge.

“If anyone has any information which they think could help with our appeal, then please call the Thames Valley Police non-emergency number on 101.”

If you have any information relating to this case, please call 101 quoting reference '43170112081', or contact Crimestoppers anonymously.