Ars Technica:

Apple has pulled the latest watchOS 3.1.1 update after some users reported that it bricked their Apple Watch.

Unfortunate users that installed the update—which launched on Monday and promised various bug fixes—were left with watches displaying a red exclamation mark on the screen and a link to www.apple.com/help/watch. The issue appears to mostly affect the Apple Watch Series 2, although not every user has experienced problems with the update.

While not a widespread problem, it doesn’t matter if your Watch has been bricked. Apple says, “We are working on a fix for an upcoming software update” but no word on when that will be available.