Five men were arrested on Wednesday by fraud squad detectives investigating alleged corruption in football.
City of London Police said the five were being held on suspicion of conspiracy to defraud and false accounting.
The men, aged 69, 60, 55, 48 and 30, were taken into custody as officers swooped on eight addresses across the UK.
The raids were part of the force's economic crime unit's investigation into alleged bungs in the game.
Last year the FA brought in former Metropolitan Police commissioner Lord Stevens and his company, Quest, to carry out a separate inquiry into dubious transfers.
A City of London Police spokeswoman said: 'Five men have been arrested on suspicion of conspiracy to defraud and false accounting as part of an ongoing investigation into football corruption.
'One search is under way, seven additional searches at a variety of locations across the country have now been concluded.'
A 61-year-old man was held in May on suspicion of money laundering and a 28-year-old - widely rumoured to be Tottenham Hotspur defender Pascal Chimbonda - was questioned in September.
Police also searched Newcastle United, Portsmouth and Glasgow Rangers as well as two homes during a series of raids in July.
City of London Police refused to confirm the location of any of the searches or how those arrested were linked to the game.