Mamadou Chune, 55, of Berry Close, Oxford, assisted unlawful immigration and concealed criminal property between 2006 and 2016.

He worked as a supervisor for two cleaning contractors and placed illegal immigrants as cleaners in Sainsbury’s stores in Oxfordshire and Wiltshire.

Judge Michael Gledhill QC said he “took advantage” of them.

Chune, originally from The Gambia, worked for two cleaning companies responsible for providing contracts for cleaners in multiple Sainsbury’s stores.

Between 2006 and 2016 he put West African migrants up in properties he owned, with some of the workers sharing rooms and beds.

He also created false identities and falsified bank statements.

The Home Office said over a decade of activity, the gang made an estimated £600,000 profit.

Judge Gledhill QC said Chune “deliberately” and “substantially” undermined UK immigration control for his own benefit.

“Your own experience with dealing with the Home Office left you well equipped to know how the immigration system worked and how illegal immigrants could avoid detection by the authorities and obtain work to support themselves”, he said.

Three other defendants – Sabbeh Jeng, 48, from Oxford, Isaac Nimo, 41, from Bicester and Helen Tankoh, 54, from Northhampton – were given suspended jail terms for fraud offences.

Ebrima Jabang, 50, from Luton, is believed to have left the country, was given a 23-month sentence.