Fortune:

Apple is reassuring customers that its systems have not been breached while a hacker, or hackers, threaten to remotely wipe hundreds of millions iPhones of all their data, including photos, videos, and messages.

The hackers are using an alleged cache of stolen email accounts and passwords as leverage in an attempt to extort the world’s most valuable company. They claim to have access to as many as 559 million Apple email and iCloud accounts, Vice blog Motherboard reported on Tuesday.

Want to be on the safe side? Enable two-factor authentication.