(CNN) -- The shadow match fixing casts over football grew a shade darker Thursday after Britain's National Crime Agency confirmed seven arrests had been made as part of an ongoing investigation.
Two men suspected of involvement have been charged with conspiracy to defraud bookmakers by influencing the course of football matches and placing bets thereon, the NCA said Thursday. Five of the seven arrested have made bail, the agency said.
The arrests were made across Britain Tuesday and Wednesday as part of a probe into a "suspected international illegal betting syndicate," said the NCA -- Britain's equivalent of U.S. law enforcement agency the Federal Bureau of Investigation.
The NCA, which became operational in October, is working closely with the Gambling Commission and the Football Association, the organization which oversees English football.
"This is an active investigation and we are unable to provide further detail at this time."
The Gambling Commission, which regulates most gambling in Britain, is cooperating with the NCA in the investigation.
"The Gambling Commission has provided advice, intelligence and expertise in supporting this ongoing National Crime Agency investigation and continues to liaise with both the NCA and the Football Association," the body said in a statement.
An investigation by British newspaper The Daily Telegraph claimed Asian match-fixers are targeting games in English professional football's lower levels.
In a series of covert conversations recorded by the newspaper over the past two weeks, one of the arrested individuals claimed that lower league matches could be fixed for £50,000 ($81,500) and correctly forecast the outcome of three games played by the same team.
The Football League, which runs the lower leagues of English professional soccer, said it was aware of media reports but it had not been contacted by the NCA.
"We understand from media reports that there is an ongoing police investigation into alleged match fixing in domestic football," said Football League chief executive Shaun Harvey. "To date, we have had no contact from the police regarding this matter.
"The threat of corruption is a matter that the Football League and the other football authorities treat with the utmost seriousness. The integrity of our matches and our competitions is the bedrock of the domestic game."
Match fixing has plagued world soccer in recent years. Senior European crime fighters Europol announced in February it had probed 680 suspicious matches across the globe including two European Champions League matches, one of which was played in England.
In Australia, four British players who spent part of last season with clubs in the Conference South have been arrested and charged for alleged match fixing in the Victoria Premier League this year. They have been suspended by FIFA and are due in court later this month.