“I'm afraid to walk with my puppies after what happened and no one walks their animals here anymore,” says Irina.

Even though they are outlawed in Russia, dog fights continue to attract big prize-money, with some winning up to $15,000. Between fights, however, the dogs need to be kept aggressive. Hence their owners spur on their savagery between brutal bouts to the death held in secret venues.

“After we printed this account people rang us with their own stories. I suspect there are many more unreported cases – for instance an old lady whose pet is attacked is less likely to tell the police,” says local journalist Olga Sayapina from Strana Kaliningrad newspaper.

The killings at the zoo however have sparked outrage among locals. People in Kaliningrad are really shocked by this string of attacks and they are concerned that there is a concerted and defiant group of people wanting to kill animals to train their dogs.

Dog-fighting is part of a brutal underworld where sadistic savagery is played out behind closed doors. The ringleaders are one step ahead of the police, and are rarely caught them red-handed. Dog trainer Vitaly Latyshonok has trained dogs for 33 years. He says that it is humans and not dogs who are the problem.

“If dogs are well looked after then they will be good. These people run the illegal dog fights either for money or because they are disturbed,” says Vitaly Latyshonok.

On the streets of Kaliningrad people talking of locking up their animals, never letting them outside, but for those who have vulnerable farm animals, all they can do is sit and hope that their livestock won't be the next prey to unleashed fighting dogs.