WWII code 'may never be cracked'
23 November 2012 Last updated at 11:06 GMT
Experts at intelligence agency GCHQ have asked for help in de-coding a message found attached to a pigeon leg, thought to date back to WWII.
The dead bird was found in a chimney in Surrey a few weeks ago.
But without more information, the code may never be cracked, according to the BBC's security correspondent Gordon Corera.
The code is as follows:
AOAKN HVPKD FNFJU YIDDC
RQXSR DJHFP GOVFN MIAPX
PABUZ WYYNP CMPNW HJRZH
NLXKG MEMKK ONOIB AKEEQ
UAOTA RBQRH DJOFM TPZEH
LKXGH RGGHT JRZCQ FNKTQ
KLDTS GQIRU AOAKN 27 1525/6
The original transcription of this code was provided by GCHQ who have now corrected it. The code reproduced here was amended on 30 November 2012 to reflect this.