At least five rhinos died within four days in northern West Bengal's Jaldapara National Park suspectedly due to anthrax.
Wildlife officials investigated the blood smears from the carcasses and the samples have been sent to a laboratory in Kolkata.
"The rhinos were found dead between February 18 and 21. We have found no signs of foul play. The veterinarians think anthrax could be the killer but our department is not saying anything as of now," said Ujjwal Ghosh, North Bengal's Chief Conservator of Forest (Wildlife).
Anthrax is a rare but serious bacterial illness that mainly attacks animals. The eastern and north-eastern parts of India have registered odd cases of anthrax, said officials.
The 216.51 sq. km national park in Alipurduar district has around 250 one-horned rhinos. Another 50 rhinos are in Gorumara National Park in Jalpaiguri district.
"Apart from proper disposal of carcasses and sanitising the areas where the rhinos were found dead, it is important to find out the source of anthrax, if confirmed. We advise vaccination of cattle and elephants used by the forest department," said Bibhav Talukdar, chief of Assam-based NGO Aaranyak that handles a few wildlife projects in West Bengal.
Wild animals may also need to be vaccinated if the disease takes epidemic proportions, he said.
