Communications firms are being asked to record all internet contacts between people as part of a modernisation in UK police surveillance tactics.

The home secretary scrapped plans for a database but wants details to be held and organised for security services.

The new system would track all e-mails, phone calls and internet use, including visits to social network sites.

Ministers say police need new tools to fight crime but opposition MPs and campaigners have raised privacy fears.

Makers of fake anti-virus software are exploiting search engines to drive people to sites peddling 'scareware'.

Using popular and mis-spelled search terms, the criminals divert people to sites that are seeded with fake warnings about virus infections.

The pop-up warnings claim that a visitor's PC is riddled with malicious programmes and spyware.

Research suggests some criminals are making as much as $10,000 a day from fake security software.

Anyone clicking on a booby-trapped page is then instantly re-directed to the site hosting the links to the fake security software.

Once they arrive, visitors are bombarded with pop-ups warning that their PC is infected. To clear up the infection users must download and pay for anti-virus software which typically costs about $50 (£34).

Mr Ben-Itzhak said people should be very wary of any pop-up window claiming to find evidence of an infection.

"It's impossible to scan your local disk without installing software," he said.