Hackers threatening to release details of people using a cheating website may possess the records of toward two million Japanese users, it has emerged.

Hackers identifying themselves as “The Impact Team” said they had obtained the identities, photographs and messages of all of the nearly 38 million registered users of Canada-based Ashley Madison, a website which helps men and women betray their spouses with extramarital sexual liaisons. The site had more than 1.8 million members in Japan as of May.

Contacted by The Japan Times on Wednesday, Paul Keable, vice president of communications at Avid Life Media Inc., which owns Ashley Madison, said he could not confirm whether the leaked data included information about Japanese users. He offered no further comment.

In a statement Monday, the company said it had been hacked and said it had since secured its websites and closed unauthorized access points.

Ashley Madison’s Chief Executive Noel Biderman also said the company was “working diligently and feverishly” to secure the data.

The hackers demanded the site be taken offline or they would release all customer records, including credit card transactions and users’ online profiles, together with whatever they had posted to describe their sexual fantasies.

In the wake of the hacking, Ashley Madison has offered all of its members a “full-delete option” for free. Previously, the site charged members to have their profile data removed.

The Japanese branch of the Toronto-based adultery site, which offers services in 48 countries, was launched in July 2013. It attracted 120,000 users in only 10 days following the launch.

The company was established in 2001 with a slogan: “Life is short. Have an affair.”