Julian Assange is in police custody in the UK following his arrest on sex allegations at the request of the Swedish authorities.
The WikiLeaks founder was granted conditional bail by a judge in London this morning, but is still in custody awaiting an appeal of the decision being filed by Swedish prosecutors.
Assange's supporters targeted companies such as Visa, Mastercard and Paypal for cutting ties with the whistleblower website after WikiLeaks published thousands of US diplomatic cables.
UK national security advisors have warned Assange's supporters could target key government sites as he fights an extradition attempt by Swedish prosecutors.
Extra security measures have been added to UK government web services, focusing on protecting information held about private citizens, according to UK-based paper The Independent.
Members of the online collective Anonymous have indicated they are willing to attack UK targets if Assange is extradited to Sweden, the paper said.
Sarah Palin, former governor of Alaska, has claimed that her website has been targeted by London hackers avenging Wikileaks.
Palin, who has been vocal in her criticism of WikiLeaks, said her website was hit by a distributed denial of service (DDoS) attack last week.
WikiLeaks has a strong following among hackers and some form of backlash was inevitable, said Alan Bentley, senior vice-president international of global security firm, Lumension.
"The WikiLeaks saga is undoubtedly set to continue for some time and all organizations involved will want to beef up their security efforts in a bid to protect themselves from the wrath of the hactivist community," he said.
This story was first published by Computer Weekly