LONDON (Reuters) - Two tennis umpires were banned last year, one for life, for breaches of the sport's Code of Conduct for Officials, governing body the International Tennis Federation (ITF) said on Tuesday.
Four other umpires are under investigation by the Tennis Integrity Unit (TIU), the London-based ITF said.
The sport is already reeling from revelations in a report by the BBC and BuzzFeed in January that 16 players who have been ranked in the top 50 had been repeatedly flagged to the TIU over concerns they had thrown matches.
Tennis authorities rejected allegations that evidence of match-fixing had been suppressed or had not been properly investigated over the past decade, although they recently announced an independent review of integrity in the sport.
The specter of match umpires possibly colluding with betting syndicates by manipulating live scoring data at low-ranking events, as alleged in Britain's Guardian newspaper on Tuesday, is a further blow to the sport's image.
The ITF said Kazakhstan's Kirill Parfenov was banned for life last February for contacting another official on Facebook in an attempt to manipulate the scoring of matches.
Croatian Denis Pitner was suspended in August for 12 months after sending information about a player to a coach during a tournament and regularly logging on to a betting account from which bets were placed on tennis matches.
In 2014 French tennis official Morgan Lamri was banned for multiple breaches of the Tennis Anti-Corruption Programme.
Explaining why the latest suspensions had only just been disclosed, the ITF said that its Code of Conduct for Officials did not require those sanctioned to be named, until the code was tweaked at the start of the year.
The ITF would not comment on the Guardian report that said umpires from Kazakhstan, Turkey and Ukraine were among those being investigated, saying that details of alleged offences would only be made public if they were found guilty.
It did respond to suggestions that a five-year deal worth a reported $70 million with data company Sportradar had inadvertently exposed tennis to corruption.
Sportradar passes on scoring data from umpires, even at bottom rung Futures circuit tournaments, to 'in-play' betting websites around the world.
The Guardian said that by deliberately delaying inputting the outcome of a point, umpires can help court-side gamblers to place bets knowing what was going to happen next.
"The ITF's data contract with Sportradar for an official data feed provides regulation and control where previously there was none," a statement said.
"Our agreement with Sportradar, like those in place with ATP and WTA, by creating official, accurate and immediate data, acts as a deterrent to efforts by anyone trying to conduct illegal sports betting and/or unauthorized use of data for non-legal purposes.
"Sportradar are excellent partners and share with the ITF the goal of ensuring the integrity of our sport."
Reporting by Martyn Herman; editing by Toby Davis