Citizens are calling for a Germany laboratory to be shut down after distressing footage showed monkeys screaming in pain.
On Saturday protesters will gather outside the Laboratory of Pharmacology and Toxicology (LPT) in Hamburg demanding the facility be closed.
Their anger will be met by hundreds of furious people online who have bombarded the lab's Google page with negative reviews.
As the sickening footage of bloody, dying animals went viral, German Minister for Agriculture Barbara Otte-Kinast suggested the facility could close.
"If these allegations prove to be true, they would have to be punished and quick consequences be put in place," she said.
"A possible revocation of the animal testing licence is being checked by Laves (Lower Saxony State Office for Consumer Protection and Food Safety.)"
The shocking footage was recorded by undercover workers from animal rights organisations Soko Tierschutz and Cruelty Free International (CFI).
In the footage monkeys are seen crying while they hang from metal harnesses strapped to their necks, before they are stuffed into tiny cages.
The eight-minute clip also shows toxicology tests being carried out on cats, dogs and rabbits, leaving them in a highly distressed state.
The animal rights charities have had success with targeting animal testing laboratories before.
Back in 2014 an undercover investigation of the conditions at a neuroscience facility in Tübingen caused people to protest in large numbers.
As a result the institute stopped its controversial monkey brain experiments.
If the fury articulated on the LPT's Google page is channelled at the protests on Saturday, then the future of the lab could be in doubt.
"Vile and evil," one person wrote.
"I only hope all these animals can have peace in their lives after going through your living hell."
Another added: "How is it even possible in 2019? I feel so bad about what I saw today, I can't imagine what those poor living creatures have endured....in the name of progress and technology?"
According to CFI, tests carried out at the laboratory involve poisoning animals to see how much of a chemical or drug it takes to cause serious harm, in an attempt to measure what a ‘safe’ dose for humans might be.
They claim the animals are injected with or made to eat or inhale increasing amounts of a substance to measure the toxic effects.
The horrific effects include vomiting, internal bleeding, respiratory distress, fever, weight loss, lethargy, skin problems, organ failure and even death.
CFI claim animals are not given pain relief or anaesthetics.
The undercover worker said staff are not trained animal carers and were often violent towards the animals.
They said they witnessed beagles bleeding after the experiments in which pipes forced were down their throat as they were given capsules.
Michelle Thew, CFI chief executive, is calling for the laws to be changed.
He said: "Our investigation has uncovered appalling animal suffering, inadequate care, poor practices and breaches of European and German law.
"We are calling for LPT to be closed.
"We are also calling for a comprehensive review into the use of animals in regulatory toxicity testing in Europe, including the UK.
"Every investigation, without fail, shows a similar tale of misery and disregard of the law."
An online petition has been launched by activist Carolin Iding that calls for LPT to be shut down.
It says: "The recent research by the SOKO Animal Welfare to LPT shows again in horrible pictures and video recordings that in my city animals are tortured and maltreated.
When I think about how animals are suffering behind the walls of the LPT right now and experiencing hell on earth right now, everything in me contracts.
"No living thing deserves to be treated like that and die like that!"
