Police officers in unmarked HGVs are focusing on the M25 for the next two weeks in a bid to improve safety standards on the motorway.
National Highways has teamed up with seven police forces across the South East, as part of Operation Orbital which uses unmarked HGVs to check drivers are not usng their mobile phones or driving without seatbelts.
Police will also carry out checks on vans and lorries for roadworthiness, secure loads, weight and drivers’ hours to reduce the risk of incidents along the route.
Police forces taking part in the operation over the next two weeks include the Metropolitan Police, the City of London Police, the Thames Valley Police as well as the police forces of Hertfordshire, Essex, Kent and Surrey.
The HGV 'supercabs', funded by National Highways, allow police officers to film evidence of unsafe driving behaviour by pulling up alongside vehicles.
Drivers are then pulled over by police cars which are following a short distance behind.
The cabs have derestricted speed limiters, which means they can travel at speeds up to the national speed limit, and have flashing lights for use in an emergency.
Colin Evans, regional road safety coordinator for National Highways in the South East, said: "Over 7,500 vehicles travel round the M25 every hour, ranging from commuters getting to work to haulage firms delivering goods along the route or overseas.
"The vast majority of drivers obey the law but a few are risking potentially devastating consequences by not carrying out appropriate checks before setting off or by driving dangerously.
"The two weeks of action will see enforcement agencies carrying out checks along the M25 to help improve safety for everyone."