LONDON : Newcastle United was one of three clubs raided by British detectives as part of a probe into alleged corruption in football, police said on Monday.
The City of London Police, handling the investigation, would not disclose which clubs were involved or which leagues they were in.
But a spokesman for Northumbria Police said they were aware that "an operation" had been carried out at St James' Park, the home of Premiership side Newcastle.
No arrests have been made, a City of London Police spokesman told AFP, adding that the raids were not connected to Lord John Stevens' ongoing Quest inquiry into Premiership transfers.
The raids, which took place between 7:30 am and 9:00 am (0630-0800 GMT), were "in regard to an ongoing investigation into football corruption by the City of London Police economic crime department", the spokesman said.
"We can confirm that search warrants were served at three football clubs and the homes of two individuals in connection with corruption in football and its impact on owners and shareholders.
"This investigation is a totally independent inquiry.
"It has not been influenced or informed by the Quest inquiry in any way.
"As this is a live investigation, it would be inappropriate to comment further at this stage."
He said the investigation was launched in late 2006. One person has been arrested so far, a 61-year-old man who was bailed until October.
That arrest was on suspicion of money laundering and was not related to the main focus of the investigation, he said
The City of London Police is handling the probe as it is the national lead force for fraud investigation.
Former Scotland Yard chief Stevens presented a report to the FA Premier League last month, which identified 17 transfers as suspect.
The deal which took Didier Drogba to Chelsea, the "super-agent" Pini Zahavi and Newcastle boss Sam Allardyce were all left facing further investigation.
The report, drawn up following a 15-month investigation, identified five clubs - Chelsea, Newcastle, Bolton, Middlesbrough and Portsmouth - as having acquired players in deals which could not be cleared as legitimate.
But Stevens, who examined a total of 362 transfers for evidence of wrong-doing, concluded there was no evidence of illegal payments to club officials or players and said all the clubs named had fully co-operated with his investigation.
The former police chief did however express serious concerns over the conduct of 15 agents, including Zahavi, an Israeli agent who is one of the most high-profile figures in the game.