Google has not yet thoroughly deleted all the private information it had gathered in a "mistake" committed while collecting images for its Street View service.

In 2010, it was revealed that Google had collected 600GB of "payload data" (i.e. audio, video, documents and emails) from unsecured Wi-Fi networks as it drove around Australia to capture images for its mapping service.

Communications Minister Stephen Conroy at the time called it the "single greatest breach in the history of privacy," and he accused Google of deliberately making such lapse in operations.

Australian Privacy Commissioner Timothy Pilgrim is pushing Google to "immediately destroy the data" and enlist a third party to confirm that all the data has been destroyed.

Google promised over a year ago that all the data had been deleted, but it turns out this is not quite accurate. The giant internet firm has recently written to Pilgrim to let him know not all the data had been erased.

Google: 'It was an innocent mistake'

When the news of Google's seemingly underhanded data collection first came out, the company admitted having "screwed up."

Google's CEO at the time Eric Schmidt admitted Google "screwed up," but he described it as an innocent mistake. Still, he blamed a male software engineer who wrote the code behind the data collection for the mapping.

Same Google "mistake" in other countries

The same mistake happened in Britain, Ireland, France, Belgium, the Netherlands, Norway, Sweden, Finland, Switzerland and Austria.

Britain's Information Commissioner's Office said, "[Google's] failure to secure its deletion as promised is cause for concern."

Pilgrim to Google: 'Just destroy the private information'

Google has earlier offered affected countries the option to look at the gathered data before it is removed. Other countries have reportedly taken the offer, but Pilgrim has told Google to just have all the data destroyed immediately.