Following the charging of four men with conspiracy to defraud in Conference South games, a national newspaper claims to have evidence of fixing attempts in the Championship
The National Crime Agency (NCA) confirmed in a statement that it has begun looking into fresh claims after being passed material by a national newspaper.
The newspaper claimed to have evidence of a player willing to arrange a yellow card in a Championship fixture in return for money.
A statement from the NCA read: "The NCA can confirm that The Sun on Sunday has passed material from its own investigation to the National Crime Agency.
"An active NCA 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."
The Football League released a statement of its own in response to the allegations made in the press, with chief executive Shaun Harvey saying: "We treat any allegations of criminal activity in our competitions with the utmost seriousness.
"Given that there is an ongoing Police investigation into this matter, we cannot comment further at this time, although we would encourage anyone with any evidence to report it to the Police.
"We will be giving our full assistance to the Police during their investigation."
The NCA is already conducting a separate investigation into alleged football match-fixing, after launching a probe into a suspected international betting syndicate in November.
Four men, including two Conference South players, have been charged with conspiracy to defraud as part of those inquires.