According to a 2007 newspaper report, Source Columba (Latin columba, "pigeon") was the code name

Code name

A code name or cryptonym is a word or name used clandestinely to refer to another name or word. Code names are often used for military purposes, or in espionage...

 for the Confidential Pigeon Service, an unconventional British

Great Britain

Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...

 intelligence gathering operation in World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

.

It involved air-dropping homing pigeons behind enemy lines in German

Nazi Germany

Nazi Germany , also known as the Third Reich , but officially called German Reich from 1933 to 1943 and Greater German Reich from 26 June 1943 onward, is the name commonly used to refer to the state of Germany from 1933 to 1945, when it was a totalitarian dictatorship ruled by...

-occupied France

France

The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

 and Holland as a means for locals to convey information, such as troop movements, to British intelligence. From 1940 onwards, hundreds of pigeon cases were parachuted into Europe, each case including – apart from the pigeon – sheets of very thin paper, a special pencil and a tube for storing the message, as well as French

French language

French is a Romance language spoken as a first language in France, the Romandy region in Switzerland, Wallonia and Brussels in Belgium, Monaco, the regions of Quebec and Acadia in Canada, and by various communities elsewhere. Second-language speakers of French are distributed throughout many parts...

 and Dutch

Dutch language

Dutch is a West Germanic language and the native language of the majority of the population of the Netherlands, Belgium, and Suriname, the three member states of the Dutch Language Union. Most speakers live in the European Union, where it is a first language for about 23 million and a second...

 instructions on how to fill in a report. A recent copy of a London

London

London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...

 newspaper was also included as proof of good faith.

In 1944, prior to the imminent Allied invasion

Operation Overlord

Operation Overlord was the code name for the Battle of Normandy, the operation that launched the invasion of German-occupied western Europe during World War II by Allied forces. The operation commenced on 6 June 1944 with the Normandy landings...

, German counterintelligence sought to counteract (or co-opt) Source Columba by dropping pigeons of their own. These pigeon cases, accompanied by a packet of English cigarettes, were purporting to be British also and carried instructions to communicate the names of the local patriots to the Allies. The Résistance

Resistance

- Physics :* Electrical resistance, a measure of the degree to which an object opposes an electric current through it* Friction, the force that opposes motion** Drag , fluid or gas forces opposing motion and flow...

, for its part, let it be known that the best way to deal with these false birds would be to smoke the cigarettes and eat the pigeons.

Despite such interference, the operation was reported to have been remarkably successful, yielding useful intelligence in over fifty percent of the received messages. 31 Source Columba pigeons eventually received the Dickin Medal

Dickin Medal

The Dickin Medal was instituted in 1943 in the United Kingdom by Maria Dickin to honour the work of animals in war. It is a bronze medallion, bearing the words "For Gallantry" and "We Also Serve" within a laurel wreath, carried on a ribbon of striped green, dark brown and pale blue...

, the highest British military decoration for animals. The operation became public only after National Archives

The National Archives (UK)

The National Archives is a UK government department and an executive agency of the Secretary of State for Justice. It is "the UK government's official archive, containing 1,000 years of history"...

files relating to it were released in 2007. However the method and a few actual cases were described in some detail in Dr R.V. Jones' autobiographical book Most Secret War (Hamish Hamilton, London) in 1978.