Undercover police caught a lorry driver watching a documentary on his mobile phone while travelling on the M5 on Wednesday, May 12.

The driver, who was was given a ticket for not being in proper control, was just one of 70 people caught committing offences on the motorway by an unmarked police lorry last week.

Gloucestershire Constabulary stopped dozens of people without insurance or seatbelts and for speeding, insecure loads and using their mobile phone.

Sergeant Lucy Powell said: "The vantage point that we got from the cab allowed us to detect offences that we might not see from our normal patrol vehicles, particularly with heavy goods vehicles and larger vans.

"The use of the cab was a really great tool for keeping the roads of Gloucestershire safe."

She added: "Drivers using a phone behind the wheel are four times more likely to be involved in a collision, far less likely to notice and react to hazards, more likely to show poor lane discipline and make more variable speed choices.”

Police filmed the offending drivers before notifying an accompanying marked police car which intercepted them.

The police operation, named Tramline, took place between May 10 and May 15 in partnership with Highways England.

The use of a mobile phone whilst driving is one of the 'fatal four' causes of road deaths and injury in the County along with inappropriate speed, not wearing a seat belt and drink/drug driving.

Last year 181 mobile phone usage tickets were issued with a further 20 people receiving tickets for not being in proper control of the vehicle with an additional 34 people being prosecuted after not paying the fine.

Operation Tramline has caught over 4000 distracted drivers so far this year after they were seen to be committing a variety of offences including driving while using mobile phones, not wearing a seatbelt, speeding and drink or drug driving.