Internet search engine Google has caused outrage after admiting copying household computer passwords and emails.
The company collected the information from wireless networks when its vehicles drove around residential streets taking photographs for its worldwide Street View product, which was launched in 2008.
Anti-surveillance campaigners have described the error as “outrageous” and the privacy watchdog has launched an investigation.
It is not yet known whether UK homes were affected by the security breach.
Alan Eustace, Google’s vice-president of engineering and research, said: “We want to delete this data as soon as possible, and I would like to apologise again for the fact that we collected it in the first place.
“We are mortified by what happened.”
Google, which is based in California, admitted in May that it had collected information about the name and location of wireless networks not protected by passwords.
But now seven privacy regulators have analysed the data and revealed the full extent of what was copied.
Mr Eustace said: “It’s clear from those inspections that while most of the data is fragmentary, in some instances entire emails and URLs [web addresses] were captured, as well as passwords.
“We want to delete this data as soon as possible.”
A spokesman for privacy watchdog the Information Commissioner’s Office said: “We will be making inquires to see whether this information relates to the data inadvertently captured in the UK before deciding on the necessary course of action, including a consideration of the need to use our enforcement powers.”
Alex Deane, director of privacy campaign group Big Brother Watch, said: “As if building up a database of photographs of millions of people’s private homes wasn’t enough, the news that Google has also harvested email addresses and passwords is nothing short of outrageous.
“Google must launch an urgent investigation as to how this gross invasion of privacy was allowed to happen.”