The FBI is disputing a computer hacker group's claim that it stole personal identification data on millions of Apple device owners from an FBI agent's laptop.
The FBI says it never asked for and never possessed the database that the group, which calls itself AntiSec, is posting on a website.
The group released a link to a database of more than 1 million Apple device identification numbers.
Federal officials are warning that computer users should be careful when clicking on such links because they may sometimes contain malware that can infect computers.
AntiSec is a hacker group affiliated with Anonymous, a collection of Internet-savvy activists who have struck out against governments, officials or corporations over a variety of political grievances.
Apple did not respond to repeated requests for comment.