Fearing Maoists attacks, Indian forest officials have moved 22 sloth bears from West Bengal to the south.
It took four days for the 12 male and ten female bears to be brought from Purulia to the Bennerghatta national park, near Bangalore, some 2000km away.
Forest officials decided to rescue the animals because they felt they were under threat, the zoo's director said.
The bears were moved after warnings from a conservation group who feared they were at risk from Maoist rebels.
"The threat was real," SOS Wildlife's founder, Kartick Sathyanarayan, told the BBC.
"The Maoists had put up a poster saying: 'Leave the forest if you want to remain safe'," he said.
Maoists, he said, were believed to be behind a 2009 attack on Jhargram Zoo, in West Bengal, during which many animals were burnt alive.
A vet from the group said the bears had initially been placed under quarantine as a precautionary measure.
"They were evacuated with the help of three large trucks. A team of about 12 trained staff with a veterinary doctor travelled with the bears to ensure their safety and to keep a check on their health," Dr Arun A Sha said.
Mr Kartick said the evacuation was carried out with the help of the communist-ruled West Bengal government.
"It is heartening that the animals have been saved. Authorities realised the gravity of the threat," he said.
The Bannerghatta National Park, home to tigers, lions, and elephants, now has a total of 117 sloth bears, with the arrival of the rescued bears from West Bengal.
The park is also considered an important corridor for elephants migrating between the eastern and western mountain ranges of southern India.