Derby County have revealed that a member of Leeds United's "footballing staff" was caught at the Rams training ground on Thursday.
Frank Lampard's pre-match preparations for Friday evenings Championship clash were disrupted yesterday morning after a man was caught acting suspicious outside the club's training facility.
Derbyshire Police confirmed that a man had been escorted away the premises after they were called to the training ground at 11:20am, tweeting: "Officers were called at around 11.20am on Thursday, January 10, to reports of a man acting suspiciously outside the @dcfcofficial training ground on Morley Road, #Derby. A man was found at the perimeter fence of Moor Farm and was spoken to.
"Officers conducted routine checks which were all above board. Despite media reports, no damage to the fence was found, and the man was stopped outside the grounds. No arrests were made and the man was sent on his way."
The Rams have now confirmed the matter themselves and since revealed that they believe it was in fact a member of Leeds United's staff.
A club statement said: "It has since been confirmed to Derby County that the individual concerned is an employee of the footballing staff at Leeds United Football Club.
"The club is now in discussion with Leeds United club officials in relation to this incident.
"At this time no further comment will be made."