The facial recognition technology that could identify people through their social media profile

New facial recognition technology created by a "secretive" company has been supplied to law enforcement agencies to help identify unknown people through their social media images, according to a report.

Clearview AI co-founder Hoan Ton-That's invention has ripped billions of images from Facebook and other sites.

The app allows people to take and upload a photo of someone, which then links that image to other photos posted to the internet. The New York Times reports that a link is then provided showing where those images came from.

Clearview AI, which is described in The NYT report as a "tiny" company, is linked to controversial US tech billionaire and NZ citizen Peter Thiel. He was granted Kiwi citizenship under the previous National Government having only spent 12 days in the country.

Jeremiah Hall, a spokesman for Thiel, said however he was not directly tied to the company.

"In 2017, Peter gave a talented young founder $200,000, which two years later converted to equity in clearview AI," Hall told The NYT.

"That was Peter's only contribution; he is not involved in the company."

The New York Times reports that agencies including police officers in Florida have been supplied with the app, but it's raised questions about privacy and safety. Since the newspaper report, Facebook has confirmed it would investigate the technology.

"Scraping Facebook information or adding it to a directory are prohibited by our policies, so we are reviewing the claims about this company and will take appropriate action if we find they are violating our rules," a spokesperson told Business Insider.

Thiel is still on the Facebook directors' board, according to CNN. He was a controversial figure in the US in 2017 when he became one of the prominent business people to support the presidential campaign of Donald Trump.

Thiel's connection to New Zealand is mostly financial. He invested about $50 million in accountancy software company Xero and the New Zealand Venture Investment Fund.

His citizenship allowed him to purchase a 193-hectare estate in Lake Wanaka in 2015 with Overseas Investment Office approval.