Courtesy Bletchley Park Trust

This coded message from World War II was found in November enclosed in a canister attached to the leg bone of a dead carrier pigeon.

LONDON — A note written in code that was found on the skeleton of a carrier pigeon dating from World War II has been cracked, according to a Canadian history enthusiast.

Originally discovered in November, the message was enclosed in a red canister attached to the leg bone of the carrier pigeon. David Martin found the pigeon in the chimney of his home in Surrey, England.

The U.K. Government Communications Headquarters (GCHQ), one of Britain’s three national intelligence agencies, said at the time that the handwritten message “cannot be decoded without access to the original cryptographic material.”

But Gordon Young, from Peterborough, Ontario, set his mind to deciphering the message using his great-uncle’s World War I code book.

"It follows same sort of code they used in the first war," Young told NBC News. "I’m not saying my note is perfect, but I am saying the code is crackable and this one is pretty close."

Experts: Unbreakable code message found on WWII carrier pigeon

It took Young, the editor of a local volunteer history group, 17 minutes to understand the message, which consists of 25 five-letter code groups.

He believes that the message was sent one afternoon in 1944, not long after the Allied landing at Normandy. It was written by an officer who was dropped behind enemy lines, confirming an earlier lunch-time note he sent giving the map coordinates of the Germans’ guns and tanks. It also confirmed that several units of American and British troops had finally met up.

In addition to using his uncle’s code book, Young double checked with infantry maps online to confirm his hypotheses.

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"To really understand the exact circumstances of the note, we would need access to British and American war diaries from the time," he said.

'Impossible to verify'
Despite Young’s translation, the GCHQ still maintains that without the original codebooks the note is indecipherable.

“We stand by our press notice of 22 November 2012 in that without access to the relevant codebooks and details of any additional encryption used, the message will remain impossible to decrypt,” a spokesman for the GCHQ told NBC News in an emailed statement. “Similarly it is also impossible to verify any proposed solutions, but those put forward without reference to the original cryptographic material are unlikely to be correct.”

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The pigeon is thought to have been part of a flock of 250,000 that were used to carry messages between the European front and Britain during World War II.

"I am hoping that this will stir up some interest in the bravery of the men who were dropped on the battlefield," said Young.

"Imagine a guy dropping down behind enemy lines with crates of pigeons and a couple of bags of feed. How they didn’t get caught is amazing. It wasn't like today where there are unmanned drones. These guys were risking their lives," he added.

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LONDON — A coded message from World War II found on the leg of a dead carrier pigeon in an English chimney cannot be deciphered, according to British intelligence agents.

The handwritten message on a small sheet of paper headed "Pigeon Service" was found earlier this month in a small red canister still attached to the pigeon's leg, the GCHQ agency said in a statement posted on its website.

The pigeon is thought to have been one of the 250,000 used by British forces — including secret agents working behind enemy lines in German-occupied Europe — during the 1939-1945 war.

The message was signed and appears to say "Sjt W Stot", GCHQ said, adding that nothing is known of this individual or their unit. Sjt is an abbreviation of the old-fashioned "serjeant" spelling of the army rank.

Royal Pigeon Racing Association, courtesy Bletchley Park Trust

This coded message from World War II was found in a canister still attached to the leg of a dead carrier pigeon.

'Tribute' to code-makers
It was destined for a place code-named "X02," but it is also not known what this means. It contains 27 five-letter code groups, but GCHQ said it was impossible to decipher the message without the relevant code book.

"During the war, the methods used to encode messages naturally needed to be as secure as possible and various methods were used," the agency's statement said.

"The senders would often have specialist code books in which each code group of four or five letters had a meaning relevant to a specific operation, allowing much information to be sent in a short message. For added security, the code groups could then themselves be encrypted," it said.

"Although it is disappointing that we cannot yet read the message brought back by a brave carrier pigeon, 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," it added.

Courtesy Bletchley Park Trust

This coded message from World War II was found in a canister still attached to the leg of a dead carrier pigeon.

It is thought a "one-time pad" may have been used to encrypt the message.

"The advantage of this system is that, if used correctly, it is unbreakable as long as the key is kept secret. The disadvantage is that both the sending and receiving parties need to have access to the same key, which usually means producing and sharing a large keypad in advance," GCHQ said.

The pigeons carried a wide variety of messages, "flying the gauntlet of enemy hawk patrols and soldiers taking potshots at them to bring vital information back to Britain from mainland Europe," GCHQ added.

Each had its own identity number and the Bletchingley message contains two such numbers — NURP.40.TW.194 and NURP.37.OK.76. Either could be the dead pigeon's number.

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