Police have reportedly raided both Newcastle’s St James’ Park and West Ham’s London Stadium over suspect transfer dealings.
HM Revenue and Customs have launched an investigation into the two clubs, with Newcastle managing director Lee Charnley arrested last night following the probe.
Charnley has overseen the Magpies’ promotion back to the Premier League at the first time of asking this season.
They clinched their return with a 4-1 win over Preston on Monday night.
A statement from HMRC read: “HMRC has arrested several men working within the professional football industry for a suspected Income Tax and National Insurance fraud.
“180 HMRC officers have been deployed across the UK and France today.
“Investigators have searched a number of premises in the North East and South East of England and arrested the men and also seized business records, financial records, computers and mobile phones.
“The French authorities are assisting the UK investigation, have made arrests and several locations have been searched in France.
“This criminal investigation sends a clear message that, whoever you are, if you commit tax fraud you can expect to face the consequences.
“As this is an ongoing investigation HMRC is unable to provide any further detail at this time.”