A family helped run a major fraud operation spanning more than a decade which deprived Royal Mail of around £70 million, a court has heard.

Parmjeet Sandhu, 56, and his nephew Balginder Sandhu, 46, were part of a scheme to under-declare mail posted through a network of logistics companies in Buckinghamshire and Berkshire, pocketing millions of pounds, it is alleged.

They worked under Parmjeet Sandhu’s brother, owner of Packpost International Ltd and “architect” of the fraud, Narinder Sandhu, who has already pleaded guilty, prosecutors told a jury.

Parmjeet, director of sister companies Tiger International Logistics Ltd and Worldwide Transport Express Ltd, and his nephew, Balginder, owner of Global Express Worldwide Ltd, took part, it is alleged, as allegedly did a third man, Lakhwinder Sekhon, 42, who is not a family relation.

The trio appeared for trial at Southwark Crown Court, central London, on Tuesday charged with conspiracy to commit fraud by false representation between 2008 and 2017.

Prosecutor Ellis Sareen said “thousands” of items were under-declared by manipulating docket spreadsheets, beginning in 2005 and lasting until 2017 when Royal Mail investigators uncovered discrepancies.

He said: “In this case, we will be talking about literal tonnes of mail – thousands of thousands of items.”

Parmjeet Sandhu operated from a warehouse in Slough, Berkshire, where his companies were based, while Balginder Sandhu was also “integral” to the scheme, it is alleged.

Sekhon is alleged to have helped Narinder Sandhu find properties in which he could invest profits from the fraud.

The three deny the charges and the trial continues.