Computer hackers are trying to blackmail internet bookmakers by threatening to disrupt online betting ahead of the Grand National.
The hackers, believed to be criminal gangs in Eastern Europe, are threatening to paralyse bookmakers' websites unless their demands for money are met.
The extortion racket is being investigated by the National Hi-Tech Crime Unit (NHTCU).
A spokeswoman for the NHTCU said: "We know that specific sporting events are being targeted. This could well include the Grand National and Euro 2004."
The criminals' method is a co-ordinated electronic attack, flooding websites with requests for information.
The attack slows down the sites to such an extent that users are effectively unable to place a bet.
If successful, the attacks could cost bookmakers hundreds of thousands of pounds in lost business.
The gangs are also understood to be threatening to disrupt online betting ahead of other major sporting events this year, such as the Euro 2004 football tournament.
They make the threats via email, demanding around £20,000 to £30,000, around an hour's worth of business for the bigger internet bookmakers.
The hackers use what is known as a Distributed Denial of Service attack, where targets are deluged with requests for information, paralysing their website for 24 hours.
The hackers, believed to be criminal gangs in Eastern Europe, are threatening to paralyse bookmakers' websites unless their demands for money are met.
The extortion racket is being investigated by the National Hi-Tech Crime Unit (NHTCU).
A spokeswoman for the NHTCU said: "We know that specific sporting events are being targeted. This could well include the Grand National and Euro 2004."
The criminals' method is a co-ordinated electronic attack, flooding websites with requests for information.
The attack slows down the sites to such an extent that users are effectively unable to place a bet.
If successful, the attacks could cost bookmakers hundreds of thousands of pounds in lost business.
The gangs are also understood to be threatening to disrupt online betting ahead of other major sporting events this year, such as the Euro 2004 football tournament.
They make the threats via email, demanding around £20,000 to £30,000, around an hour's worth of business for the bigger internet bookmakers.
The hackers use what is known as a Distributed Denial of Service attack, where targets are deluged with requests for information, paralysing their website for 24 hours.
