It has been a busy seven or so days at Fratton Park. Last Monday, players, manufacturers and the media attended the launch of the new kit; on Wednesday David Nugent and John Utaka, the newly signed forwards, arrived to be paraded to the press; and yesterday it was the turn of plain-clothes police to pay a visit.

The officers inspected documents at the club’s new offices at Rodney Road, which have replaced the antiquated facilities behind the well-known half-timbered Frogmore Road façade. “We can confirm that the police arrived at about 10am,” Gary Double, Portsmouth’s director of communications, said. “We have cooperated fully with their search and will not be commenting further.” Portsmouth also claimed that the two warrants served at the houses of individuals were unconnected with the club.

It was a low-key occasion, with no blaring sirens – “all very pleasant and courteous” according to a club source – but still an unwelcome one for a club in a state of upheaval since the transfer of ownership early last season to Alexandre Gaydamak from Milan Mandaric, now the owner of Leicester City.

Although Gaydamak, who bought half of the club in January 2006, remains a mysterious figure who seldom speaks publicly and has never revealed the source of his funds, it is understood that the investigations centre on events that took place before he appeared on the scene.

Harry Redknapp, the Portsmouth manager, is also believed to have been employed elsewhere when the dealings in question took place. He left Fratton Park after a disagreement with Mandaric in November 2004, taking over at Southampton and being replaced by Velimir Zajec, and then Alain Perrin.

Perrin, who is now in charge at Lyons and will manage in the Champions League this season, was relieved of his duties in November 2005 and Redknapp returned the next month. Last season Redknapp was featured in the BBC Panorama investigation into football transfers, but no evidence was produced to suggest that he had been involved in any dishonesty.

The only recent transfers between Portsmouth and the other two clubs under investigation involved Newcastle United. Three involved players moving south: Lomano LuaLua moved from St James’ Park to Fratton for £1.7 million in July 2004 after being on loan; Laurent Robert spent six months on loan to Portsmouth in 2005, while Andy Griffin moved south on a free transfer in May 2004.

However, most attention is likely to focus on the move of Amdy Faye from Fratton Park to Newcastle for £2 million in January 2005. Redknapp signed the Senegal midfield player from Auxerre in summer 2003 after playing him under an assumed name in a friendly, and he was hailed as a new Patrick Vieira as he proved a capable ball-winner during the club’s maiden Premiership season. However, he was allowed to leave after Redknapp’s departure, but he failed to live up to his early reputation after his move to the North East. He subsequently joined Charlton Athletic.

It was mid-morning when news of the investigation reached the training ground at Eastleigh, where Redknapp is reported to have had a heated exchange with LuaLua after the player turned up late for training. The Democratic Republic of Congo forward is said to have planned to lodge a transfer request, only to be advised that minds at Fratton Park were elsewhere.