Veterinary specialists in the Russian city of Krasnoyarsk are investigating why two giraffes in the city's Royev Ruchei zoo have died in the space of just a week, the zoo's Marina Shilikova told RIA Novosti on Wednesday.

"Two giraffes have died in a week. We've set up a commission today to study the causes of this tragedy. Park specialists and experts from Krasnoyarsk's veterinary service will investigate this, to find out what caused their death," she said.

The zoo’s Director, Nikolai Kulakov, said the occurrence of two deaths in the animals in a week was just a coincidence.

“We lost two giraffes in a week but this is just a wild coincidence,” he said. “In the first giraffe an autopsy revealed a heart defect, low kidney function, a small heart and lack of organ development. No pathological changes were noted in the autopsy of the second one, but video-surveillance cameras showed there was some kind of conflict between the two of them. Stress can lead to death of an animal in these circumstances,” he said.

Six giraffes from South Africa were brought to the park in 2007, and were an instant hit with the public in Krasnoyarsk. The city's zoo is one of the largest in Russia, covering 74 acres (30 hectares).