A former postmaster says his family felt threatened and he felt compelled to sign a false confession admitting to stealing thousands of pounds during the Post Office scandal.

Senapathy Narenthiran was given a three-year prison sentence after the company accused him of stealing thousands of pounds from the tills.

The 68-year-old says he felt he had no choice but to sign a confession letter after he believed he and his wife would both be jailed, and his children subsequently taken into care, if he didn’t.

The former postmaster recalled: “I was told: ‘You know what will happen Mr Narenthiran if you don’t write the letter. The first thing is you will be taken into custody, the second thing is your wife will be, because she also works there, and then your children will go into custody.’”

Mr Narenthiran, who now owns and operates a shop in Ramsgate, says the Post Office insisted he owed the company £275,000, but he denied any wrongdoing.

He said: “I told them I never took any money, but they said you must be having a bad habit of, you know, giving out money or gambling or drinking.”

More than 700 branch managers were given criminal convictions after faulty accounting software used on Post Office computers made it appear as though money was missing from their shops.

Mr Narenthiran, who worked at a Post Office in East London between 2005 and 2006, spent 18 months behind bars at HMP Standford Hill on the Isle of Sheppey.

He says the experience of being in prison still affects him, as does having a criminal record.

“Still, there is a black mark,” he continued.

“Even when I look at my kids, my wife, they know that I have been inside and I don't know how they react and all these things.

“I applied for a visa to go to Canada but they straight away rejected me because I have been inside prison.

“It’s not right at all - we haven't committed any crime.”

This comes after it was revealed Paula Vennells, who headed the Post Office while it routinely denied there were problems with its IT system, will hand back her CBE honour after a petition signed by one million people called for her to do so.

The petition, which is addressed to Sir Chris Wormald, the chairman of the Forfeiture Committee, says: “Evidence has been produced that the Post Office engaged in a mass cover-up which led to the wrongful prosecution of 550 Post Office staff many of whom were subsequently jailed, bankrupted and in some cases, sadly took their own lives.

“Having been handed a CBE for services to the Post Office, and moved out into other senior positions in government and healthcare, it is only right that this award is now withdrawn through the process of forfeiture.”

There has been a fresh public backlash to the scandal after ITV aired a drama starring actor Toby Jones last week about the ordeal.

Reports suggest since Mr Bates Vs The Post Office was broadcast, 50 new potential victims have approached lawyers.

The Post Office is wholly owned by the government and a public inquiry into the Horizon software is ongoing.

Speaking during a visit to Oxford on Sunday, the Prime Minister said the UK government was “keen to do everything we can because this was absolutely appalling” and should “never have happened”.

Rishi Sunak said: “It has been an appalling miscarriage of justice and appalling treatment of all the people affected and it is right that they get the redress that they deserve.”

When asked about the allegations made by Mr Narenthiran, a spokesperson for the Post Office said they would not comment on individual cases, but provided the following statement: “We are doing all we can to right the wrongs of the past, as far as that is possible.

“Both Post Office and government are committed to providing full, fair and final compensation for the people affected.”

Additional reporting by Sofia Akin and Bartholomew Hall