Italy-based Bangladeshi migrants are accused of making millions of pounds by misusing the UK's taxpayer funded welfare schemes, prompting authorities to arrest 13 people following a probe.
Each claimant is said to have received an average of 9,000 pounds (USD 13,868).
The migrants are believed to have attended interviews at Jobcentres in London to get national insurance numbers which are compulsory to claim any state-funded support.
Hundreds of Bangladeshis have been flying to Britain from Italy for the day to con the system out of millions of pounds in housing benefit.
Five organisations, including a charity, are suspected of providing fake job details to help the fraudsters, 'The Sun' newspaper reported.
London-based Asma Khanam, 46, a trustee of Families for Survival UK, was among 13 arrested as part of the investigation and has already appeared before Redbridge magistrates.
Several people were expected to appear in court this week charged with conspiracy to defraud after a joint investigation by Scotland Yard, the Department for Work and Pensions (DWP) and Redbridge council in east London, the report said.
The charity's website says that it runs projects in Bangladesh and Kenya, as well as supporting elderly and disabled people in the UK.
The investigation is believed to have discovered many of the claimants left the country hours after lodging their benefit claims.
It is said that fraudsters allegedly made millions of pounds over three years. Councils such as Newham and Tower Hamlets are probing whether they have been defrauded.
The migrants obtained EU citizenship in Italy before flying to London and using one address in east London to carry out their scheme.
An investigation was started after reports of a significant number of Bangladeshis with Italian passports arriving at Stansted airport with return flights booked for the same day.
"Our fraud investigators have powers to track benefit cheats around the world and bring them before the courts.
"We are determined to crack down on people who abuse the system, so that benefits only go to those who really need this help. In addition to any sentence imposed by the courts, fraudsters must pay back all the money they falsely obtained and face a criminal record for life," a DWP spokesperson said.
Scotland Yard has refused to comment at this stage.
