Six kangaroos were killed, three of them females carrying young, when a pack of stray dogs broke into their enclosure at a Russian zoo, the zoo's chief vet said Friday. Five were mauled to death while a sixth smashed into the side of the enclosure in a panic and died, Svetlana Yarova told RIA Novosti. "The dogs mauled them to death not because they were hungry, but their hunting instinct kicked in," said Yarova, chief vet at the zoo in the western city of Kaliningrad. Guards ran up but were too late to save the animals, she said. They found a fresh hole dug under the fence. The zoo had suffered from stray dog attacks in the past, Yarova said, with a lama and a deer dying in previous years. "We have a problem with dogs. And of course there's not enough money to go round, as usual. Our fence is old as well," she said. Russia's Soviet-era zoos are outdated and keep animals in small enclosures often in the centre of cities.