Under the UK Terrorism Act 2000 - which came into force yesterday - computer hackers could be punished as terrorists.

A Home Office spokesman said: "There isn't a specific section that deals with cybercrime as such, it is covered within the various sections. Anyone who seriously interferes with, or seriously disrupts an electronic system will be dealt with under the anti-terrorism law."

The Terrorism Act extends the definition of what is legally terrorism. It can now include hackers or political protestors if their actions or intentions "turn violent", the spokesman said. Political analysts feel hunt saboteurs and anti-roads protestors could be charged under the act.

Police powers Police now have the authority to determine what they deem to be "violent" and who they feel comes under the legal definition of a "terrorist".

The vague nature of the Terrorism Act immediately came under criticism from opposition politicians.

Simon Hughes MP, Liberal Democrat shadow Home Secretary, said: "The legislation, which gives the authorities extra powers, should have to be renewed by parliament regularly rather than being permanent legislation. The definition of terrorism is also far too wide, in spite of significant efforts by Liberal Democrats and others in parliament to improve it.".