Pictured: Gang of 20 jailed for £8m tax and money laundering scam

The 17 men and three women, from across the Black Country, Staffordshire, Birmingham and Manchester, were arrested by HM Revenue and Customs officers during Operation Savate, an investigation that revealed tax offences and money laundering linked to the construction industry over a two-year period.

Investigators uncovered a large and complex web of illegal activity involving more than 100 businesses across the country.

Subcontractors were employed 'off-record' and the gang members pocketed Income Tax and National Insurance contributions due to be paid to HMRC.

At the same time fake invoices, supposedly for providing labour, had also been created to claim VAT refunds to which the gang were not entitled.

Amongst those who have been jailed are Bernard Harper, 57, from Causey Farm Road, Halesowen, who Judge Peter Carr described at sentencing as being at 'the centre of the fraud and an organiser of it'.

He was jailed for eight years in September after a 17-week trial at Birmingham Crown Court, and disqualified for acting as a company director for 10 years.

The convictions of those behind the scam can only be reported now after legal restrictions were lifted following the conclusion of three trials.

Colin Booker, assistant director of criminal investigation at HMRC, said: "The final sentencing brings to an end a six-year investigation, centred on a highly organised and complex fraud, undertaken by a group of individuals who cared for nothing but their own financial gain."