Russia is experimenting with a bizarre "spy rocks" - listening devices once used by British intelligence in Moscow.
New footage shows a fake stone designed by Moscow’s military researchers for use against its enemies.
“Due to its disguise and ability to change position, it can come in handy in trench warfare,” reported the Russian Defence Ministry’s TV channel Zvezda.
The robot rock can be controlled by radio signals from an operator more than a mile away and is moved into position when the enemy is not watching.
It has cameras and listening capabilities, say its designers at the Air Force Academy from Voronezh under the guidance of the Scientific and Technical Committee of the Main Directorate of Combat Training of the Armed Forces.
It is officially known as an “observation complex” with an electronic eye that raised like a periscope.
The device was christened a “spy rock” by the military TV channel.
Nothing similar is currently used by the Russian armed forces, said the channel, which showed one of the designers Nikolai Yemets demonstrating the rock.
"The main problem was getting all the equipment we needed into a small rock," he said.
The idea appears to be taken from a sophisticated British snooper stone famously found in a Moscow park by Russian secret services.
A Russian “traitor” had been spotted walking near the rock and was later accused of transmitting classified information to the spy rock which was seen as having been planted by MI6.
The unusual spy tool can be used discreetly without other people being aware of it.
It was reportedly bristling with advanced equipment to retrieve and store signals sent from transmitters carried by passing Russians spying for the British.
State TV in Moscow gleefully highlighted the spy rock, and claimed a British diplomat had been caught red-handed checking the stone.
The episode led to the expulsion of four British diplomats in 2007 - worsening relations between the two countries.
Five years later ex-premier Tony Blair ’s then chief of staff Jonathan Powell unusually admitted to the hi-tech espionage attack on Russia.
“The spy rock was embarrassing, they had us bang to rights,” he told the BBC.
“Clearly they had known about it for some time and had been saving it up for a political purpose."
When the rock was first found, it created concern among diplomats.
British ambassador at the time, Sir Tony Brenton, later admitted the rock’s discovery was “a considerable headache”.
"The Russians chose their time carefully and it was politically very damaging," he explained.
