So far less than 100 megabytes of data have been published but the hackers claim to have over eight gigabytes.

Links to the material were first posted on Twitter by @anonesc, one of many accounts that make announcements about the activities of Anonymous, a hacking collective that claims to have no formal leadership or structure.

Another Anonymous-linked account, @AnonymousIRC, tweeted its support, saying “#AntiSec strikes at Italy government”.

“Silent no more,” it added.

AnitSec” is Anonymous’ campaign against governments and the security industry.

The CNAIPIC files purport to contain information on an array of firms involved in critical infrastructure, including oil and nuclear firms, as well as government bodies such as the Australian Ministry of Defence. The authenticity of the documents has not been independently confirmed.

The release follows the arrest earlier this month of 15 alleged members of Anonymous by Italian authorities, part of a global crackdown on the collective.

A public statement attributed to Anonymous at the time said: “Those arrested are not ‘dangerous hackers’ as the media calls them, but people like you. They have been arrested while peacefully protesting for their and your rights. Our protest will continue louder than ever.”

CNAIPIC is yet to comment on the claims.

Anonymous, which is believed to have branches in several countries, gained prominence after it launched retaliatory attacks on companies perceived to be enemies of whistle-blowing website Wikileaks. Its Italian branch is suspected of online sabotage against the country’s parliament, senate and large companies like the state oil major ENI, according to La Republica.

Last week Anonymous claimed to have breached network security at Nato. An investigation is ongoing.

Source: Telegraph News