A lioness and eight Indian tigers died while being transported to a circus show in the city of Yakutsk in Russia`s Siberia, a local police spokesman said on Tuesday, according to RIA Novosti.
The animals were in a container on board a Kamaz truck traveling from Khabarovsk to Yakutsk and were completely neglected by the circus staff who accompanied them on the trip.
"An investigation is underway. Preliminary data indicates that the animals could have died from inhaling exhaust fumes," the source reported.
A Sakhacircus official said the animals died from suffocation and hypothermia.
"The exotic animals were kept in a container without air-conditioning or heating. The lioness and tigers had inhaled exhaust fumes and froze to death, while a Himalayan bear sow survived, however is in serious condition," the official said.
The temperatures in the region at the time of the incident were as low as minus 38 degrees Celsius (minus 36 Fahrenheit).