Fraud police have now launched their own formal investigation into allegations  involving public money at a high-profile multi-academy trust (MAT).

The investigation into the Bright Tribe Trust is being carried out by City of London Police - which is the country’s lead force for major fraud investigations.

The force told Tes it had decided to start a formal investigation after its fraud unit completed a review of a file relating to Bright Tribe which had been passed to it by Cumbria Police.

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The investigation into Bright Tribe - which once ran 10 academies - relates to allegations of fraud using public funds.

Bright Tribe’s current leaders have said the police investigation is looking at allegations dating back to the previous leadership of the trust.

A spokesperson for the City of London Police said: “I can confirm that our officers have reviewed the information provided by Cumbria Police and a formal investigation has begun.”

The City of London Police said last month that Cumbria Police had provided it with information about Bright Tribe. But it is only now that the start of a full investigation has been revealed.

Bright Tribe was one of the government’s chosen sponsors to raise standards in the North of England and one of five MATs given extra funding to establish a hub of schools in the North.

However, it has since pulled out of all its schools after facing a series of controversies over standards, finances and  the condition of school buildings. The trust, which is under new management, has now given up control of all of its academies.

Last year, it emerged that the Department for Education was trying to recover up to £321,775 from Bright Tribe because it did not have proof that the money was spent on its intended purpose.

A Bright Tribe spokesperson said: “Interim trustees and executive leaders were appointed to the trust almost 18 months ago - working with the Department for Education, they quickly and successfully stabilised all aspects of the trust and its schools, and achieved the transfer of all the trusts’ schools to strong new academy trusts, providing thousands of children and young people with the high-quality education they deserve.

“We are aware that the police are investigating historic matters relating to the previous leadership. While the investigation is ongoing, it is not possible to comment further.”