I have learned that News International yesterday sacked former head of news at News of the World Ian Edmondson. His dismissal followed an investigation into his possible involvement in the illegal hacking of mobile phones.

After an extensive trawl of his e-mails, News International has found what sources described as "highly damaging evidence". This has been passed to the police and is understood to lie behind the decision of the police to reopen the hacking inquiry.

Update 1720: Here's a bit more information about the sacking of Ian Edmondson.

At 1000 yesterday investigators from News International found e-mails that allegedly show that Mr Edmondson had knowledge of attempts to hack into the mobile phones of prominent individuals by the private investigator Glen Mulcaire.

News International confronted Mr Edmondson with the e-mails and dismissed him at 1600.

The UK arm of Rupert Murdoch's News Corporation then sent the new evidence to the police. And it is this information which is the basis of the fresh police enquiry announced today.

There can now be no doubt that News International has abandoned its previous position that it had uncovered everything there was to find about possible malpractice in the way the News of the World tried to uncover information about the private lives of celebrities and public figures.

It now appears to be aggressively investigating the involvement of its employees in a way it didn't do hitherto.