The Information Commissioner's Office (ICO) has reopened its investigation into Google after the search firm admitted that its Street View cars had collected more personal details than was first revealed.
Google said in a blog post on Friday that full emails, URLs and passwords had been gathered, prompting the UK privacy watchdog to step in for a second time.
The ICO visited Google's premises in July to make a preliminary assessment, but did not take any further action.
"Whilst the information we saw at the time did not include meaningful personal details that could be linked to an identifiable person, we have continued to liaise with, and await the findings of, the investigations carried out by our international counterparts," an ICO spokesperson said in statement.
"We will be making enquires 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."
Google, meanwhile, has taken steps to strengthen its internal privacy and security practices to ensure that it learns from its mistakes, according to Alma Whitten, Google's director of privacy.
"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," she said.
"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, as well as to answer their further questions and concerns."
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