Computer hackers attacked News International websites this week including tabloid The Sun.
Computer hackers attacked News International websites this week including tabloid The Sun, forcing staff to change passwords and tighten security.
Hacking group LulzSec redirected The Sun's online readers to a fake page which reported News Corporation CEO Rupert Murdoch had been found dead in his garden.
The hackers took responsibility for the attack in messages posted via the social networking site Twitter and said they was preparing more online assaults.
"Within 20 minutes, pages are overloading, things are crashing! We are working our way through the cracks right now. Stay tuned for more," LulzSec said on Twitter.
"We have joy, we have fun. We have messed up Murdoch's Sun," another of their Twitter postings said.
They also posted jokes and abusive messages about Murdoch and his media empire, both caught up in a phone-hacking scandal that has rocked Britain's establishment right up to Prime Minister David Cameron.
Two sources inside Murdoch's print headquarters in London said staff at Murdoch's newspapers, including the Sunday Times, had been told to change their passwords.
A spokesperson for News International, parent company of The Sun, The Times and The Sunday Times, declined to comment on the security measures.
"We are aware of the hacking attempt on the sun.co.uk last night and our sites are now back up.
"We do not have any further comment to add at this time."