Detectives hope the jailing of the Johnson gang will help bring to an end a crime spree which has spanned the last 20 years.

Daniel O’Loughlin, 31, was already serving seven-and-a-half years for metal thefts when he stood trial for the mansion burglaries. He also had previous convictions for making a false declaration in respect of a £71,000 Porsche car, handling stolen goods, burglary and dangerous driving.

Chad Johnson, 32, also pleaded guilty in the metal theft case and was jailed for five years and three months. In addition, the father-of-four, a talented artist, was already serving three years and six months after marrying an heiress more than twice his age.

He sold her flat and emptied her bank accounts, leaving her bankrupt. He pleaded guilty to conspiracy to defraud at Bristol Crown Court in March 2007.

Ricky Johnson, 54, had 22 previous convictions for 57 offences dating back to 1965. He had convictions for burglary and violence when he was a youngster and regularly appeared in court for deception offences until the 1980s. His last conviction was for conspiracy to defraud in 1997.

Michael Nicholls, 29, had 17 convictions for 28 offences, including burglaries in 1994 and 1997 and deception in 2003.

Albi Johnson, 23, had also served jail terms for offences including burglary and theft between 2000 and 2003. In all he had 10 previous convictions for 19 offences. In October 2005 the police forces of Gloucestershire, Thames Valley, Warwickshire and West Mercia decided to pool resources to bring an end to the gang’s criminality in Operation Haul.

Detectives spent hours trawling through mobile phone records, CCTV footage and speed cameras pictures to painstakingly piece together a case.

Detective Superintendent Mark Warwick, who led the investigation, said the Johnsons were forensically aware and left little evidence of their crimes.

In all, the team investigated 116 offences of country house burglaries, cash dispenser and metal thefts which occurred in all five force areas between January 2005 and August 2006.

Since the arrests in 2006, Thames Valley Police have seen a 90 per cent reduction in offences attributable to the group and across all areas there has been a dramatic decrease in country house burglaries, cash machine and metal thefts.