A Battersea businessman who threatened and robbed his accountant at gunpoint after they refused to commit fraud has been jailed for more than six years.

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

His partner, Monika Piatkowska, 33, also of Kingfisher Walk, was found guilty of conspiracy of perverting the course of justice after trying to silence Mysliwiec's victims with payments to keep quiet.

She was sentenced to two and a half years in prison.

In April 2014 Mysliwiec, a Polish national who ran a ventilation manufacturing company in Dospel, flew to the UK with two colleagues to try to persuade his accountant to submit false VAT invoices.

After the accountant refused, Mysliwiec returned to the Edmonton office days later accompanied by four men armed with guns.

Along with another employee the accountant continued to refuse despite threats from Mysliwiec, who warned him he would be answerable for about £300,000 a month in losses if he did not cooperate.

Mysliwiec then ordered another employee into the office, before assaulting him with builder's tools and tying him up.

The mob left the office with £10,000 in cash, as well as several iPhones, an iPad, car keys, and a Polish ID card.

The victims reported the ordeal to the police, who were able to arrest Mysliwiec at Luton airport the next time he flew to the UK.

After the arrest Piatkowska, the head of Polish company registered to an address in Walthamstow, flew to the UK to support Mysliwiec.

While she was in London she arranged for a private detective to trace the families of the three robbery victims back in Poland.

When one of the victims was approached by Piatkowska and the private detective, they gave a statement to their solicitor withdrawing their allegations against Mysliwiec in fear of what might happen to their family.

But the victim also went to the police, who later arrested Piatkowska at a meeting between her and the victim just after she had handed him several thousand pounds in sterling and Polish zloty.

Ross Moultrie, from the Metropolitan Police's 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.

"Mysliwiec banked on his accountant assisting him in his criminality, but when this was refused, his three victims were subjected to a terrifying experience.

"This was a complex case which demonstrates the commitment and dedication of the Flying Squad to investigate anyone who believes they can threaten others and pervert the course of justice in this way."

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