Personal details of more than 10.6 million former guests of MGM Resorts hotels, including Justin Bieber and Twitter’s chief executive, Jack Dorsey, were posted on an online hacking forum this week, according to a new report.

The details published include full names, home addresses, phone numbers and emails, the tech news outlet ZDNet reported on Wednesday. Those targeted include high-profile figures such as Dorsey and Bieber, as well as regular tourists, reporters and FBI agents.

ZDNet said it verified the authenticity of the data with a security researcher from Under the Breach, a soon-to-be-launched data breach monitoring service.

MGM owns and operates luxury resorts in Las Vegas, as well as other locations in the United States, Japan and China. Its Las Vegas resorts frequently draw thousands of guests for casino tournaments, boxing matches and UFC fights.

An MGM spokesperson told ZDNet that the information comes from a security incident that happened last year after MGM “discovered unauthorized access to a cloud server that contained a limited amount of information for certain previous guests of MGM Resorts”.

The data reportedly contains no information from guests who stayed at the resorts after 2017.

While sizable, the security incident is not the largest to hit the hotel industry in recent years. In 2017, a data breach at the Marriott hotels saw Chinese state-sponsored hackers steal the information of up to 500 million guests.

Catalin Cimpanu, the ZDNet reporter behind the story, wrote on Twitter that the information published was leaked in July 2019, a month before customers were notified of the breach.

Exclusive: Details of 10.6 million of MGM hotel guests posted on a hacking forum



- Leak took place in July 2019

- Customers notified in August 2019

- Leak traced back to a misconfigured cloud server

- Data was posted online this weekhttps://t.co/z6HLJfVW5V pic.twitter.com/9UpFOr9t42 — Catalin Cimpanu (@campuscodi) February 19, 2020

MGM told ZDNet that it is confident that no financial or password data was involved in the security incident.

MGM did not immediately respond to the Guardian’s request for comment.