Washington, Sep 14 (IANS) The Central Intelligence Agency (CIA) has declassified details of its secret Cold War spy-pigeon missions, revealing how pigeons were trained for clandestine operations photographing sensitive sites inside the Soviet Union and dolphins for underwater missions, the media reported.

According to the BBC, the files also reveal how ravens were used to drop bugging devices on window sills. The report says that the CIA believed animals could fulfil "unique" tasks for the agency's clandestine operations.

The newly-released files show that the 1970s' operation was codenamed Tacana and explored the use of pigeons with tiny cameras to automatically take photos.

It took advantage of the fact that the humble pigeon is possessed of an amazing ability - almost a superpower. They can be dropped somewhere they have never been before and still find their way hundreds of miles back home.

The use of pigeons for communications dates back thousands of years but it was in World War I that they began to be used for intelligence gathering, the BBC reported citing the files.

In World War II, a little known branch of British intelligence - MI14(d) - ran a Secret Pigeon Service which dropped birds in a container with a parachute over Occupied Europe. A questionnaire was attached. More than 1,000 pigeons returned with messages including details of V1 rocket launch sites and German radar stations, reveal the files.

One message from a resistance group called Leopold Vindictive produced a 12-page intelligence report sent directly to former UK Prime Minister Winston Churchill. After the war, a special "Pigeon Sub-Committee" of Britain's Joint Intelligence Committee looked at options for the Cold War.

But while British operations were largely shut down, the CIA took over in exploiting pigeon power.

The files reveal that later the CIA trained a raven to deliver and retrieve small objects of up to 40g from the window sill of inaccessible buildings.

A flashing red laser beam was used to mark the target and a special lamp was used to draw the bird back. On one occasion in Europe, the CIA secretly delivered an eavesdropping device by bird to a window (although no audio was picked up from the intended target).

The CIA also looked at whether migratory birds could be used to place sensors to detect whether the Soviet Union had tested chemical weapons.

According to the BBC, it also appeared there were trials of some kind of electric brain stimulation to guide dogs remotely, although many of the details were still classified.

A previously reported operation called Acoustic Kitty involved placing listening devices inside a cat.

In the 1960s, the files show the CIA looked at using dolphins for "harbour penetration" either manned or unmanned. One problem was in handing over control from a trainer who had worked with a dolphin to a field agent.

There were also tests on whether dolphins could carry sensors to collect the sounds of Soviet nuclear submarines or look for radioactive or biological weapons traces from nearby facilities. They also looked at whether dolphins could retrieve or place packages on ships on the move.

By 1967, the CIA was spending more than $600,000 on three programmes -- Oxygas for dolphins, Axiolite
involving birds and Kechel with dogs and cats.

Pigeons proved the most effective and by the mid 1970s the CIA began flying a series of test missions. One was over a prison, another over the Navy Yards in Washington DC.

--IANS soni/