The National Crime Agency has confirmed that three people are in custody following allegations of spot-fixing in English football.
It was reported by The Sun that a match in the Championship had been fixed, with a player arranging for his teammates to get booked in exchange for money.
Three people have now been taken into custody after the newspaper passed material onto the crime-fighting organisation.
"The NCA can confirm that the Sun on Sunday has passed material from its own investigation to the National Crime Agency," read an official statement from the NCA.
"An active investigation is now under way and we are working closely with the Football Association and the Gambling Commission. We cannot comment further at this stage."
Two non-league players were charged last week in relation to separate allegations of match-fixing.