A Facebook glitch briefly told users that they had died this evening (Friday 11 November) in a "terrible" error that even affected Facebook CEO Mark Zuckerberg.

The bug caused the social network to show a memorial banner above user profiles for people that were actually still alive.

"We hope people who love (Facebook user) will find comfort in the things others share to remember and celebrate (his or her) life," the banner read on some profiles for a few hours.

The message, intended to be read on "memorialised profiles", appeared on the profile pages of thousands including on Zuckerberg's.

The switch to memorial pages left social media users shocked and confused, with some swiftly posting status updates to reassure friends and family they had not died.

A Facebook spokesman said afterwards: "For a brief period today, a message meant for memorialized profiles was mistakenly posted to other accounts. This was a terrible error that we have now fixed. We are very sorry that this happened and we worked as quickly as possible to fix it."

The widely used memorial feature was introduced by the social media giants last year. It was in response to a number of high profile cases where family members wanted to access posts, pictures and data pertaining to dead loved ones.

Every Facebook user can opt into having the memorial page option when they die to inform friends after a "legacy contact" changes your account. Facebook can also delete your account after your death, if you wish.

Tech news website Gizmodo reported that even after the fix that some users were "reporting that their Facebook friends who actually died are popping up as alive". It is not clear how many users were affected by the glitch.

Many in the Tech world took to social media rivals Twitter to poke fun at the awkward incident which left users across the globe "dead".