Gangs across London are making millions by banging into innocent motorists to make bogus insurance claims.

A list of national "hotspots" released by the Insurance Fraud Bureau (IFB) show there were an estimated 22,603 incidents nationally from 1999-2006.

883 of those were in south west London and In west London the figure was 834.

Only 200 incidents occurred in south east London.

Blackburn is believed to be the area worst affected in the country with an estimated 1,710 incidents.

Nationally fraudsters are believed to be making £350 million a year using a method known as "slamming".

A gang member drives in front of the innocent car and brakes quickly, causing the front car to be hit in the rear.

Passengers then act as "witnesses" to the incident.

Tory MP and chairman of the parliamentary taskforce on fraud, John Greenaway, said: "People think insurance fraud is a victimless crime, but it isn't.

"And it really is only a matter of time before someone is killed."

The IFB data was collated from 38 insurance companies, linking people and vehicles persistently involved in claims.