Ex-Premiership footballer DJ Campbell is among six people questioned by police in connection with allegations of fixing in football matches.
Mr Campbell, who plays for Championship side Blackburn, was one of six people arrested on Sunday.
The arrests came after ex-Portsmouth player Sam Sodje told a reporter he could arrange for players to be booked or sent off in exchange for cash.
The National Crime Agency said five people were bailed later on Sunday.
Officers were continuing to question a sixth individual, who was arrested on Sunday evening, the NCA added.
Portsmouth Football Club said it was “shocked and saddened” by the claims.
Mr Campbell, 32 – whose full name is Dudley Junior Campbell – played in the Premiership for Birmingham, Blackpool and QPR.
Blackburn Rovers FC said in a statement: “Following reports in today’s national media, Blackburn Rovers can confirm that striker DJ Campbell has been arrested.
The club will be making no further comment on what is now an ongoing legal matter.
Red card
Police have not named the other five people who are being questioned.
Mr Sodje was secretly filmed by the Sun on Sunday describing how he had punched an opponent in a League One game to get a red card in exchange for £70,000.
He was sent off in the 50th minute of a League One match while playing for Portsmouth against Oldham Athletic on 23 February.
His team was losing 1-0, which remained the final score.
The paper also reported that an Oldham player, Cristian Montano, apologised to Mr Sodje after failing to get a yellow card in the first half of a match against Wolves on 22 October.
And it said that Mr Sodje’s brother Akpo, a striker at Tranmere Rovers, had said he would be prepared to be paid to be booked.
The allegations prompted the National Crime Agency to launch an inquiry.
An active NCA investigation is now under way and we are working closely with the Football Association and the Gambling Commission, it said in a statement.
‘Shocked and saddened’
In a statement from Portsmouth Football Club, spokesman Colin Farmery said: If these serious allegations are true then we are extremely shocked and saddened by them, as match-fixing of any type goes to the heart of the integrity of the game.
The player in question no longer plays for the club and we have not been contacted by the authorities, but of course we would co-operate fully with any inquiry.
Mr Montano’s club, Oldham Athletic, said it would be starting an immediate internal investigation.