CODEBREAKERS at GCHQ have been left stumped by a pigeon-borne message believed to have been sent during the Second World War.
Experts at the spy centre say they cannot decipher the message without access to the codebooks used to create it.
The message was discovered attached to the remains of a pigeon leg in a chimney in Surrey a few weeks ago.
A GCHQ spokesman said: "Unfortunately, much of the vital information that would indicate the context of the message is missing.
"It is undated, and the meaning of the destination – given as 'X02' – is unknown.
"Similarly, while the sender's signature appears to say 'Sjt W Stot', nothing is known of this individual or their unit."
He added: "It is a tribute to the skills of the wartime code-makers that, despite working under severe pressure, they devised a code that was undecipherable both then and now."