Google was accused of spying on households yesterday after it admitted secretly copying passwords and private emails from home computers.
The internet search giant was forced to confess it had downloaded personal data during its controversial Street View project, when it photographed virtually every street in Britain.
In an astonishing invasion of privacy, it admitted entire emails, web pages and even passwords were 'mistakenly collected' by antennae on its high-tech Street View cars.
Privacy breach: Google has admitted that its Street View cars also took people's emails and passwords
Privacy campaigners accused the company of spying and branded its behaviour 'absolutely scandalous'.
The Information Commissioner's Office said it would launch a new investigation. Scotland Yard is already considering whether the company has broken the law.
Google executive Alan Eustace issued a grovelling apology and said the company was 'mortified', adding: 'We're acutely aware that we failed badly.'
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Critics seized on the admission as the latest example of technology's ever-expanding ability to harvest information about ordinary households, often without their knowledge or consent.
Google sent a fleet of specially equipped cars around Britain in 2008, armed with 360-degree cameras to gather photographs for its Street View project.
There were immediate complaints that the pictures were a security risk, after householders complained that house numbers and car registrations were easily identifiable.
Privacy fears followed when it emerged that individuals could be seen, including a man emerging from a sex shop in London's Soho, three police officers arresting a man in Camden, North London, and children throwing stones at a house in Musselburgh, Scotland.
Earlier this year the California-based firm admitted that the cars' antennae had also scanned for wireless networks, including home wi-fi, which connect millions of personal computers to the internet.
Google registered the location, name and identification code of millions of networks and entered them into a database to help it sell adverts.
The firm - which uses the slogan 'Don't be evil' - was able to record the location of every wireless router and network without alerting households because wi-fi signals are 'visible' to other internet devices, including the cars' antennae.
Google played down the significance of the wi-fi mapping and insisted it had not collected or stored data from personal computers.
It then backtracked and said its software had 'inadvertently' collected fragments of data which were being transmitted as the cars criss-crossed Britain.
The cars' antennae skipped networks five times a second, it said, meaning each network was only accessed for one-fifth of a second.
But it has now emerged that entire emails, web pages and passwords were copied and stored during that split-second.
The information was only gathered from wireless networks which were not password-protected.
But it means the antennae potentially harvested millions of private emails and passwords around the country. It is not known how many householders have unprotected wireless networks.
'The company must launch a full inquiry and produce a public report on exactly what happened, as well as release the audit it has already undertaken.
'There are a lot of questions that need to be answered about how and why the company did this.'
Google's cars collected wi-fi network locations in more than 30 countries. The firm insisted the private data was not analysed or used for any commercial purpose.
It has previously blamed an engineer who inserted a rogue computer code in the Street View cars' software, and said it was a 'clear violation' of the company's code of conduct.
The Street View project has triggered privacy investigations around the world. In Australia, the country's communications minister Stephen Conroy said the data harvest was the 'single greatest breach in the history of privacy'.
Privacy regulators in seven countries analysed the data following complaints about the Street View scheme, and it was their investigations which forced Google's latest admission.
In Britain, Privacy International lodged a complaint with Scotland Yard earlier this year. Officers are still considering whether a crime has been committed.
The Information Commissioner said it would investigate Google's latest admission. If the firm is found to have breached privacy, it could face a fine of up to £500,000.
Google, which made a profit of £4.5billion last year, said its Street View cars no longer collected any type of wireless information, and promised to improve its privacy policies.
Daniel Hamilton, campaign director at privacy group Big Brother Watch, said: 'The harvesting of sensitive personal information like this is completely unacceptable.
'Google is fast developing a reputation as a company that cares little for privacy or data security.'
Paul Allen, editor of Computeractive magazine, said Google's antennae could 'see' any information that was not protected by encryption.
Secure websites, such as banking sites, could not be accessed and any activity on password-protected networks was also safe.
He said: 'Google should have realised at the outset that this was possible, and taken steps to guard against it. But consumers should also ensure their network has a password.'
Google's new director of privacy, Alma Whitten, said: 'We are profoundly sorry for having mistakenly collected payload data from unencrypted networks.
'As soon as we realised what had happened, we stopped collecting all wi-fi data from our Street View cars and immediately informed the authorities.
'This data has never been used in any Google product and was never intended to be used by Google in any way. We want to delete the data as soon as possible and will continue to work with the authorities to determine the best way forward.'
"We all formulate our thoughts, opinions, perspectives and actions based on what we know, and what we Need-to-Know is that our knowledge base has been altered in an effort to control us." - Cathy O' Brien