Cash for crash frauds are when fraudsters fake accidents by making unnecessary emergency stops at busy roundabouts or slip roads, forcing other motorists to crash into them. Then the fraudster makes a bogus claim for fictitious injury - such as whiplash - to the driver and passengers.

After Barking, the next most popular place for this kind of car fraud is a spot on the North Orbital road in St Albans, followed by the A40 intersection with the North Circular - also known as Hanger Lane Gyratory.

These are followed by a junction of the A5 in Bedfordshire; Junction 4 of the M61 in Bolton; roundabouts in Oldham and Warrington; a junction in Little Aston, Birmingham; part of the A4177 towards Warwick and the A10/A121 roundabout.

Four of these (St Albans, Little Aston, A4177 and Bedfordshire) are rural locations which fraudsters believe wrongly are less monitored and thus they are more likely to get away with it.

Paul Hubbard, head of counter fraud operations at Direct Line, said: "Our investigation systems mean that we can pinpoint areas of concern and the hot spots are just a small proportion of the data that we share with the rest of the insurance industry.

"We will not tolerate fraudsters and always push for the harshest penalties, as we have a duty to protect our customers."

Cash for crash scams are estimated to cost the insurance industry £350 million a year and this means honest drivers pay more in premiums. It also means that claims for incidents at these hotspots take longer to pay.