The company behind a controversial facial recognition software which had been used by GTA police services, including the Toronto police, suffered a data breach.

Clearview AI confirmed the news to CTV News Toronto on Wednesday afternoon.

In a statement, the company's lawyer Tor Ekeland said: "security is Clearview's top priority. Unfortunately, data breaches are part of life in the 21st century. Our servers were never accessed. We patched the flaw and continue to work to strengthen our security."

According to The Daily Beast, who first reported the story, Clearview AI sent its customers a notification saying someone had 'gained unauthorized access' to its list of customers, the number of user accounts those customers had set up, and the number of searches its customers have conducted.

Toronto police, who confirmed that several officers had informally tested the software without Police Chief Mark Saunders’ knowledge for months, said it was not used "for live streaming or real-time information gathering and there were no costs associated with its use."

"The Toronto Police Service is undertaking a full review of its use of Clearview AI and is consulting with the Information and Privacy Commissioner's Office and the Crown Attorneys' Office to consider all aspects of this technology, and its application to police investigations," Toronto police spokesperson Meaghan Gray said in a statement Wednesday.

“Our current review includes a comprehensive analysis of each time the technology was accessed by an investigator”

Clearview AI has been under scrutiny for collecting billions of public images from the Internet to build a proprietary image search tool, which it sells to law enforcement.

The company became a subject of a New York Times report last month, revealing that more than 600 law enforcement agencies, including the FBI and the Department of Homeland Security, as well as a handful of financial companies, have been using the software.

"The tool could identify activists at a protest or an attractive stranger on the subway, revealing not just their names but where they lived, what they did and whom they knew," the Times reported.

Several social media sites had sent cease-and-desist letters to the company.

Police services in Peel, Durham, and Halton have also previously confirmed that they had used the software.

Ontario's privacy commissioner Brian Beamish had said it is collaborating with all its federal and provincial counterparts "to develop guidance on the use of emerging biometric technologies, including facial recognition, by the private sector or public sector organizations."

Last week, federal and three provincial privacy commissioners launched an investigation into Clearview AI in the wake of media reports.

Privacy officials said the reports had "raised questions and concerns about whether the company is collecting and using personal information without consent."

The investigation will be undertaken by the Office of the Privacy Commissioner of Canada along with provincial counterparts in Alberta, British Columbia, and Quebec.