A Polish couple have been jailed for threatening an accountant who refused to submit dodgy tax records and then attempting to threaten the victims into withdrawing their allegations.

Sebastian Mysliwiec, 40, of Kingfisher Walk, Battersea pleaded guilty to robbery, blackmail and false imprisonment and was sentenced to six years and three months at the Old Bailey on Friday (January 29).

His partner, Monika Piatkowska, of the same address and head of Walthamstow business Luftsturm based at Uplands Business Park, was also found guilty of conspiracy of perverting the course of justice.

The 33-year-old was sentenced to two years and six months imprisonment.

In early April 2014, Mysliwiec travelled to meet with his UK-based accountant in Edmonton on behalf of his Poland-based ventilation manufacturing company.

Mysliwiec wanted him to submit false tax invoices but he refused to do this.

He ordered his men to threaten the victim and another employee at gunpoint.

Then a further employee was tied up and assaulted by Mysliwiec with tools purchased that day from a warehouse in Walthamstow.

A total of £10,000 in cash was also stolen, along with several iPhones, an iPad, car keys and a Polish ID card.

The victims reported the incident to police and when Mysliwiec next returned to the UK he was arrested on suspicion of robbery at Luton Airport.

His partner Monika Piatkowska subsequently flew to the UK to be by Mysliwiec's side.

She then arranged for a private detective to trace the families of the three robbery victims in Poland.

One victim from the robbery was subsequently approached by the private detective and Piatkowska.

Alerted to the fact that they knew where his family lived in Poland, and frightened of what might happen should he refuse, the victim agreed to withdraw the allegations against Mysliwiec.

But he later contacted police and they arrested Piatkowska at a meeting between her and the victim.

She was set to hand him several thousand pounds and Polish zloty to withdraw his allegations.

DC Ross Moultrie of the Flying Squad, said: "This couple caused immense fear and distress to their victims and huge arrogance towards the UK justice system.

“I am pleased that they will now have to spend the next few years behind bars, reflecting on their actions.”