Six men and a woman have admitted their role in an extensive motor claims scam that threatened to defraud insurers of more than £250,000.

The case was put before Isleworth crown court, Middlesex, by Miller Pycraft's special investigations team, that discovered the fraudsters had targeted a total of 11 insurance companies.

The seven defendants, mainly from Ealing, include an English woman who is married to one of the suspects and four brothers.

All pleaded guilty on Friday to 19 charges arising from fraudulent motor claims or fictitious accidents over a three-year period. A seventh man failed to appear in court and continues to face fraud offences and charges related to benefit fraud.

The fraud was initially detected in 1999 by a claims administrator at Direct Line who recalled seeing a car used by one of the defendants entered on the insurance industry's Motor Insurance Anti-Fraud Register.

Miller Pycraft were asked to probe further and this led investigator John McCann to uncover a massive fraud that enveloped 11 insurers, including Direct Line.

All of the insurers agreed to a joint probe – Operation Granby – that spanned several months and resulted in the defendants' arrest by the Metropolitan police in August 1999.

The seven suspects in the case are expected to return to court for sentencing on March 30.

John Wagstaff, manager of the Association of British Insurers' fraud unit, welcomed the court case.

He said: “Results like this show what can be achieved when insurers work together and properly investigate cases that are passed to the police.

“It sends a strong message to organized gangs that insurance companies are not a soft target.”

Dave Moore, associate director of Miller Pycraft special investigations unit, said: “All involved in the investigation should be congratulated.”