The Lulz Security hacking group has launched an attack on the website of Rupert Murdoch's Sun tabloid, as the Australian-born media boss prepares to front a British parliamentary inquiry.

The notorious group has claimed responsibility for posting a false report claiming Mr Murdoch had been found dead in his garden on the Sun website.

Later the Sun's website was redirecting to the hacker group's Twitter feed.

"TheSun.co.uk now redirects to our twitter feed. Hello, everyone that wanted to visit The Sun! How is your day? Good? Good!" said a message on the @LulzSec account.

"We are battling with The Sun admins right now - I think they are losing," said another @LulzSec tweet.

The group, which has previously hacked the Cental Intelligence Agency's website, says the fake story is just the beginning.

"We have owned Sun/News of the World - that story is simply phase 1 - expect the lulz to flow in coming days," a message from the group warned.

The hacker collective said it was "sitting on their (the Sun's) emails" and was prepared to publicise them on Tuesday.

A News International spokeswoman said the company was "aware" of the attack on The Sun.

Later the website for the Sun's News International stablemate the Times also appeared to be down.

News International is believed to have swiftly pulled all of its websites as a precautionary measure.

Mr Murdoch's British newspaper arm has been under fire over accusations that its now defunct News of the World tabloid hacked into the phone of murdered schoolgirl Milly Dowler.

The attack came as the phone hacking scandal which has rocked Mr Murdoch's global media empire continued to dominate the headlines.

Senior London police officer John Yates, the man who decided not to reopen the investigation into the News of the World's phone hacking in 2009, resigned overnight.

Meanwhile Mr Murdoch, his son James, and former News International boss Rebekah Brooks prepared for a grilling from British MPs at a parliamentary inquiry tonight (Australian time).

Former News of the World reporter and phone hacking whistleblower Sean Hoare was found dead at his home north of London. Police said the death was not suspicious.

And British prime minister David Cameron was forced to cut short a trip to Africa to return home to answer questions about his links to Mr Murdoch's empire.