The UK's top intelligence agency has apologized after social media users spied it using an offensive word in an online quiz.
GCHQ is famed for its code-breaking prowess, playing a key role in uncovering Nazi messages during the Second World War.
However, the security body appeared to have suffered a brief lapse in concentration on Tuesday when it included a swear word in the answer to one of its regular Twitter puzzles.
The unfortunate post underlined the fourth letter in the names of the planets Mercury, Venus, Uranus and Neptune.
@GCHQ/Twitter
A GCHQ spokesman:
βWe apologize for any offense inadvertently caused by this morning's post. We deleted it as soon as we became aware of the issue."
The tweet was deleted after being online for less than 20 minutes.
I wonder why this GCHQ puzzle has now been deleted https://t.co/gcP8BXblMkβ Tony Diver (@Tony Diver) 1597741845.0
A different version, minus the swearing, was later posted online, instead underlining the fourth letter in the names of all eight planets in the Earth's solar system.
Tackle the new week head-on by having a go at our latest #GCHQPuzzle π§© #MondayMotivation https://t.co/5eB3stPJ4hβ GCHQ (@GCHQ) 1597654141.0
Twitter users were quick to mock the error.
I wonder why this GCHQ puzzle has now been deleted https://t.co/gcP8BXblMkβ Tony Diver (@Tony Diver) 1597741845.0
@Tony_Diver https://t.co/HX7prTEFl0β Matt (@Matt) 1597751689.0
GCHQ have deleted their....see you next Tuesday tweetβ matthew mulligan (@matthew mulligan) 1597741849.0
Thank you @GCHQ for a brow-raising demonstration of fallibility in your recently deleted solution to thisβ¦ https://t.co/kxFVhZxHkMβ Ben Brabyn (@Ben Brabyn) 1597742277.0
Would love to know the inside story of what was going on with the @GCHQ twitter account this morning ... https://t.co/sMiPLAqGWDβ Ruaridh Arrow (@Ruaridh Arrow) 1597742671.0
@ArrowontheHill @GCHQ I hear the bureaucrats secretly gigglingβ Ben H (@Ben H) 1597742921.0
Lesson learned, we hope!