The Inner London Crown Court has sentenced a Nigerian immigrant, Olaide Taiwo, to eight-and-a-half years imprisonment for stealing the identities of 350 people to claim £1.3m in bogus tax credits.

In what was described as the largest benefit scam of its kind, Taiwo 35 was said to have hijacked the identities while working as a security guard for a number of large national companies, Daily Mail reported on Thursday.

He was then said to have used the names to claim tens of thousands in working tax credits.

The report said the sentence was the highest ever for tax credit fraud. Taiwo is understood to have arrived illegally in Britain in 2003 with his wife.

Although three applications to stay in the United Kingdom failed, in 2005 he was granted discretionary leave to remain.

It was during this period that the scam by the father of two began. He submitted more than 300 fraudulent tax credit claims between June 2004 and July 2008 worth over £1m.

When he was arrested, investigators found an ‘identity thieves’ paradise’, with stacks of fake passports, driving licences and £70,000 in cash lying around his council flat in Camberwell, South-East London.

The property was littered with paperwork detailing the names, addresses and national insurance numbers of hundreds of people which he had taken from employee payroll records at dozens of companies around London where he had worked as a security guard.

They also found templates for making false passports, birth certificates, NHS cards and driving licences.

Taiwo used the identities to open hundreds of bank accounts for the benefits to be paid into, but HM Revenue & Customs became suspicious about the multiple tax credit applications and arrested him in July 2008.

They believe he was the ringleader of an organised criminal network which included his sister-in-law who worked for a job centre.

Taiwo also tried to leave the country but he was arrested again on August 6 last year.

Sentencing him, Judge Simon Davis ordered that he be deported at the end of jail term. Another member of the gang, Taiwo’s sister-in-law Olajumoke Ademuyiwa, was also found guilty of fraudulently obtaining tax credit payments in an earlier hearing.

Ademuyiwa, 42, opened the bank accounts into which the benefits were paid, but she is not thought to have used her role as a job centre worker to make false claims.

She is due to be sentenced in April