- Visa, PayPal, Amazon also come under attack through the night
- Card users unable to make online payments for six hours
- 5,000 'hacktivists' believed to be behind electronic onslaught
The attack was launched by a shadowy international group called ‘Anonymous’ which said MasterCard and Visa had been targeted for freezing the account of the whistleblowing site.
The devastating blow to the credit card giants came on one of the busiest online shopping days of the year.
Hackers also targeted online payment system PayPal, Amazon and a Swiss bank over the WikiLeaks row.
Up to 5,000 hackers have combined under the 'Operation Payback' umbrella to target Visa and Mastercard
Last night Visa website was also taken down for a period after it came under attack.
It is thought just a few dozen ‘hacktivists’ launched the electronic onslaught, which was taken up by other supporters.
Operation: Payback was formed in September to target groups opposed to internet piracy
WikiLeaks has been publishing classified U.S. diplomatic cables, to the fury of Washington authorities.
They have lobbied to cut off all support for the website which they are desperate to shut down.
Yesterday a spokesman for Anonymous, calling himself ‘Coldblood’, a 22-year-old computer programmer based in London, said: ‘Websites that are bowing down to government pressure have become targets.
'As an organisation we have always taken a strong stance on censorship and freedom of expression on the internet and come out against those who seek to destroy it by any means.
‘We feel that WikiLeaks has become more than just about leaking of documents, it has become a war ground, the people versus the government.
‘The idea is not to wipe them off but to give the companies a wake-up call.’
In a further communique online, Anonymous warned: ‘We will fire at anything or anyone that tries to censor WikiLeaks, including multibillion-dollar companies such as PayPal.’
The spokesman added that the group’s intention ‘was to be a force for chaotic good’.
WikiLeaks founderJulian Assange has been remanded in custody over claims that he sexually assaulted two Swedish women
The problem came about when shoppers tried to pay for their purchases and were redirected to a website run by MasterCard called Securecode.
This site was not authorising payments so the transactions could not be completed.
MasterCard declined to confirm that customers had been affected. But in a statement made to a respected website it reportedly said it suffered ‘a service disruption to the MasterCard Directory Server’ and added that ‘customers may still be experiencing intermittent connectivity issues’.
Last night MasterCard said in a statement from its HQ in New York that its systems had not been compromised by ‘a concentrated effort to flood our corporate web site with traffic and slow access’.
It said: ‘We are working to restore normal service levels. There is no impact on our cardholders’ ability to use their cards for secure transactions globally.’
This online retailer took to Facebook to warn customers they might experience problems paying for wine
A screen shot of the Mastercard website showing technical problems yesterday afternoon
A PayPal executive admitted the firm stopped processing WikileLeaks' payments after being pressured by the US State Department.
The release of US diplomatic cables has sparked fury in America
According to the website TechCrunch, the admission was greeted by a chorus of boos from the audience.
Bedier, a PayPal vice president, added: 'We first comply with regulations around the world making sure that we protect our brand.'
He claimed the State Department branded WikiLeaks illegal on November 27.
John Mueller, PayPal's general counsel, said the attacks did not affect PayPal's stance on WikiLeaks, whose account would 'remain restricted'.
DDoS attacks, which are illegal in the UK, involve overloading a website with high numbers of requests so it stops working.
Anonymous, which openly admits to using DDoS tactics, wrote on its website: 'While we don't have much of an affiliation with WikiLeaks, we fight for the same reasons. We want transparency and we counter censorship.
'This is why we intend to utilise our resources to raise awareness, attack those against and support those who are helping lead our world to freedom and democracy.
'We will find and will attack those who stand against WikiLeaks and we will support WikiLeaks in everything they need.'
The group's Facebook site, which had attracted more than one million users, was taken offline by the company for violating its terms of use.
The microblogging site Twitter, source of much WikiLeaks support, could become the next target for hackers after Anonymous posted a statement claiming: 'Twitter you're next for censoring WikiLeaks discussion.'
Some supporters accuse Twitter of preventing the term 'WikiLeaks' from appearing on the site's popular trending topics, a claim that Twitter has denied.
The hackers have pledged an 'infowar' on companies that have withdrawn support from WikiLeaks during the past week.
As well as DDoS attacks, Anonymous is helping to create hundreds of mirror sites for WikiLeaks, allowing users to continue to access the website's content via a different server.
WikiLeaks founder, Julian Assange, 39, has been remanded in custody over claims that he sexually assaulted two Swedish women.
The websites of the Swedish Prosecutor and the lawyer representing the women were attacked yesterday.
Other websites targeted included those of U.S. senator Joe Lieberman, an outspoken critic of WikiLeaks, and Sarah Palin, who said Assange should be hunted like a terrorist.
Have you been affected by the MasterCard cyber attacks? Ring 0207 9386059