Russian scientists killed and tortured thousands of animals while carrying out tests on the nerve agent which poisoned a spy and his daughter.
Experts at the Chemical Research Institute near Nukus, Uzbekistan, would make the dogs wear gas masks and walk on treadmills during the experiments.
They would give the animals Novichok, which was used to attack former double agent Sergei Skripal, 66, and his 33-year-old daughter Yulia in Salisbury.
The centre was built by the Soviets to create the nerve agent and it was abandoned by the Red Army in 1992.
Thousands of dogs were subjected to the nerve agent Novichok during experiments carried out by Russian scientists
A man works in a laboratory to research physiology in high temperatures and under high pressure at the Shikhany research centre
Early versions of Novichok were sent to the Institute of Organic Chemistry and Technology in Moscow before it was finally returned to Nukus for the experiments.
The Sun on Sunday reports that thousands of animals died after they were exposed to the potent nerve agent in.
Meanwhile, scientists also tested chemical weapons, including Novichok, on dogs at the Shikhany Institute in south eastern Russia.
US expert Judith Miller recalled her memories of seeing the dogs on the 25 treadmills in Nukus.
She went to the centre after the Soviet Union collapsed and said: ‘I saw hundreds of small cages where the dogs were held and 25 miniature treadmills.
‘The dogs were strapped to them and crammed into gas masks. Thousands died from exposure to the agent.’
Thousands of dogs were forced to walk on treadmills and were given Novichok at the Shikhany Institute in south eastern Russia (pictured)
Double agent Sergei Skripal and his daughter Yulia (pictured together) are still fighting for their lives in hospital
Mr Skripal and his daughter are still fighting for their lives in hospital following the incident which shocked the world.
And it has now emerged that Yulia was in a relationship with a man who is believed to have been working for Vladimir Putin.
Meanwhile, Foreign Secretary Boris Johnson today said that experts from the Organisation for the Prohibition of Chemical Weapons will come to the UK.
They will arrive in Britain on Monday to test samples of the nerve agent used in the poisoning.