• David Haigh has been held by police in Dubai for 18 days • Denies all claims and has not been charged

The former Leeds United chief David Haigh has been accused of financial mismanagement to the amount of $5m (£3m) by Gulf Finance House Capital, his previous employers and majority owners of the club until April this year.

Documents from the Dubai International Financial Centre have revealed the extent of the allegations against Haigh, who denies all wrongdoing despite being held in a Dubai police station for 18 days. GFHC, a subsidiary of the Bahrain-based investment bank Gulf Finance House, accuse the former Leeds managing director of fraud and embezzlement, with detailed documents alleging he fabricated at least 55 invoices to secure payments to five different bank accounts, two in Dubai and three in the UK.

GFHC claims the financial invoices relate to four different companies whose representatives have presented affidavits to the Dubai court denying that they were aware of their existence or the relative bank accounts.

Haigh, who has not been charged with any criminal offence, played a key role in GFHC’s acquisition of Leeds from Ken Bates in December 2012. He left his role as the deputy chief executive with the bank in March and departed Leeds in April after the takeover by the businessman Massimo Cellino, who he had introduced to the club.

A friend of Haigh’s said: “David has now been held in custody for 18 days, a lot of criminal allegations have been put to him but no charges whatsoever have been made. This matter which was heard yesterday [on Tuesday] is purely a civil claim and not a criminal matter and doesn’t seem to warrant a man being held for 18 days. All the allegations put to David are vigorously denied.”

The court documents allege that false invoices were made for a number of financial projects. These included “Project Bremner”, “Project Offside” and “Project Athena”, the latter set up to complete due diligence on Cellino before Leeds agreed to sell a controlling 75% stake in the club to the Italian. The court documents also allege that Haigh created a number of “false fee notes”.

Leeds were bought by Cellino for more than £30m and were in severe financial difficulty before the “King of Corn” secured the club in the face of opposition from the Football League. Under GFHC United were losing approximately £1m a month and Cellino has since undertaken rigorous cost-cutting at Elland Road.

A winding up petition against the club over a loan of £950,000 is due to be heard in court on 9 June, brought by Haigh’s consortium Sport Capital which tried to buy the club from GFHC before Cellino. The club dispute the claim.