Rupert Murdoch, whose News Corporation is facing a police investigation in Australia, has hit out at "enemies", as he called for "freedom of thought and markets".
News Corporation, the media empire that owns The Sun and the Times titles, stands accused of running a secret unit to sabotage competitors, according to 14,000 emails released to the Australian Financial Review.
The Australian communications minister Stephen Conroy said the allegations should be referred to the Australian Federal Police for investigation.
Early this morning, Mr Murdoch, 81, took to his official Twitter account to respond to every "enemy piling on with lies and libel".
He told his 207,894 followers of "Enemies many different agendas, but worst old toffs and right wingers who still want last century's status quo with their monoplies [sic]".
His comments on the social networking website were made in response to the claims of corporate hacking as News Corp attempted to take over another TV network in Australia.
Foxtel, part-owned by News Corp, is currently in the process of acquiring the rival network Austar in a $2 billion bid.
Mr Murdoch said on Twitter: "Let's have it on! Choice, freedom of thought and markets, individual personal responsibility."
The mogul, who has been on Twitter since New Year's Eve, has used the website to voice his opinions on a range of political and media issues.
Earlier this week, he criticised the Prime Minister following an expose in the Sunday Times that revealed the Conservative party co-treasurer Peter Cruddas was offering access to David Cameron for "premier league" donors.
He said: "Of course there must be a full independent inquiry on both sides. In great detail, and with consequences. Trust must be established."
The latest claims against Mr Murdoch's company suggest NDS, a technology company that was part-owned by News Corp, had a secret unit which encouraged the widespread hacking of competitors.
The practice reportedly cost rivals $AUS50m (£33m) a year and helped put at least one out of business.
The Australian Financial Review made the claims this week, as it published thousands of emails from an archive held by Ray Adams, European chief of the unit called "Operational Security" between 1996 and 2002.
Pay-TV operators worldwide, including ITV Digital in the UK and Austar in Australia, were subject to a major wave of piracy during the period.
On Monday, a Panorama documentary on BBC1 alleged that NDS hired a man who ran a piracy website and tasked him with publishing "cheat" codes on the internet, allowing viewers to "crack" their ITV Digital boxes and use the services for free.
News Corp and NDS have vigorously denied the claims.
Chase Carey, president of News Corporation, said: "“The BBC’s Panorama program was a gross misrepresentation of NDS’s role as a high quality and leading provider of technology and services to the pay-TV industry, as are many of the other press accounts that have piled on - if not exaggerated - the BBC’s inaccurate claims.
"Panorama presented manipulated and mischaracterized emails to produce unfair and baseless accusations. News Corporation is proud to have worked with NDS and to have supported them in their aggressive fight against piracy and copyright infringement.
"News Corporation fully endorses Executive Chairman of NDS Abe Peled’s attached letter to Panorama and supports NDS in clearing its name, just as the U.S. Department of Justice, a federal court jury and a federal appellate court have all done in past rulings.”