The Metropolitan Police have arrested five men, aged 15 to 26, in connection with the spate of online attacks last month carried out in support of whistle-blowing web site WikiLeaks.
The five have been arrested on suspicion of being part of the group known as Anonymous, a band of "hacktivists" who carried out distributed denial-of-services (DDoS) attacks that temporarily brought down the web sites of MasterCard, Visa and PayPal after those companies cut off financial services to WikiLeaks.
The companies had chosen to withdraw their services from the web site after its release of US diplomatic cables.
The DDoS attacks brought down these sites by bombarding them with repeated requests to load web pages. Such attacks are illegal in the UK, carrying a maximum fine of £5,000. The five males were arrested in a series of raids at 7am in the West Midlands, Northamptonshire, Hertfordshire, Surrey and London and all five are being held in custody at local police stations.
An open letter purported to be from Anonymous to the UK government claims that the DDoS attacks are not illegal, but are a new way of voicing civil protest.
"Just as is the case with traditional forms of protest, we block access to our opponents infrastructure to get our message across. Whether this infrastructure is located in the real world or in cyberspace, seems completely irrelevant to us," the statement read.
It also attempted to set the record straight on the difference between a DDoS attack and hacking, claiming that these concepts often seem to be confounded when media and policy-makers talk about Anonymous.
"Hacking as such is defined by the law as ‘unauthorised access to a computer or network', whereas a DDoS attack is simply a case of thousands of people making legitimate connections to a publicly accessible webserver at the same time, using up the entire bandwidth or processing power of the given server at once and thereby causing a huge ‘traffic jam'.
"It is clear then, that arresting somebody for taking part in a DDoS attack is exactly like arresting somebody for attending a peaceful demonstration in their hometown. Anonymous believes this right to peacefully protest is one of the fundamental pillars of any democracy and should not be restricted in any way."
The letter added that similar attacks have also been carried out against WikiLeaks itself, yet so far, nobody has been arrested in connection with these attacks, nor are there any signs of an investigation into this issue at all.
"Yet, we know exactly who was responsible for that attack," added the letter.