Hacktivist group Anonymous has claimed responsibility for outages to several government websites last night.
Various Twitter accounts that belong to the group were awash with the claims yesterday, including Anonymous Operations, an account seen by some as the group's main news outlet.
"#OpFreeAssange – Tango Down: http://homeoffice.gov.uk," stated one tweet, at the same time as the main Home Office website became unreachable for a time.
This was shortly after an earlier tweet, claiming responsibility for a temporary outage at the Justice Department's site.
"#OpFreeAssange: TANGO DOWN! http://www.justice.gov.uk/ [500 Internal Server Error]," it said.
Wikileaks founder Assange is currently staying at the Ecuadorian embassy in London. He has stated his fear that if he leaves the building he will be extradited to Sweden to face sexual assault charges, and from there be summoned to the US to answer for the fact that sensitive US government and military information was published by his whistle-blowing website.
Anonymous has used cyber attacks as an attempt to defend Assange in the past, when it attacked Mastercard's site, among others, in protest at the credit card firm's decision to stop processing payments to Wikileaks.
This is also not the first time the hacktivist collective has targeted the UK government. The Home Office and Downing Street sites were taken offline in distributed denial-of-service (DDoS) attacks over Easter this year.
At the time, the group said the attacks were in protest against the government's "draconian" surveillance proposals, and also the UK's extradition treaty with the US.
While DDoS attacks are generally thought to be an inconvenience rather than a serious threat, they can be used to mask other types of cyber attack, which are designed to steal sensitive information.