A London man described as the "world's biggest computer hacker" has been arrested.

Biggest? Does that mean he is fat or something?

The unemployed former computer engineer is accused of causing the US government $1billion of damage by breaking into its most secure computers at the Pentagon and Nasa. He is likely to be extradited to America to face eight counts of computer crime in 14 states and could be jailed for 70 years.

Most of the alleged hacking took place in 2001 and 2002. At one stage the US thought it was the work of the al Qaeda terror network.

Nope, he's not Al-Qaeda.. Keeping that in mind, here is where it gets amusing:

Friends said that he broke into the networks from his home computer to try to prove his theory that the US was covering up the existence of UFOs.

Friends said he was desperate to prove that the Americans had mounted a huge cover-up to deny his belief that aliens had visited earth.

"He's been interested in UFOs for some time and believes the Americans are holding back information - although he didn't find any proof."

"The truth is out there."