Security intelligence firm Stratfor has warned subscribers that its website could stay offline for a week or more.
The website went offline on 24 December. Stratfor recently emailed subscribers informing them the website will take over a week to restore, according to emails reported by Reuters on Thursday.
"As part of our ongoing investigation, we have also decided to delay the launching of our website until a thorough review and adjustment by outside experts can be completed," Stratfor said. "An unauthorised party illegally obtained and disclosed personally identifiable information and related credit card data of some of our paying subscribers."
Hacker group Anonymous took credit for the hack. It published the personal details of over 50,000 people and promised that more data would be leaked.
Stratfor has provided affected subscribers with a free year of coverage of CSID identity and fraud protection technology, according to the email.