India's tigers are increasingly under threat
Two tiger cubs have been found dead in mysterious circumstances at the Ranthambhore national park in the north-west Indian state of Rajasthan.
Wildlife officials say it appears the cubs had been poisoned. An inquiry has been ordered.
The bodies of the cubs have been sent for post mortems.
Poaching and loss of habitat in India have decimated tiger numbers which are estimated to have fallen from 40,000 to about 1,400 in the past 100 years.
A major awareness campaign has been launched to halt the steep decline in tiger numbers in India.
Ranthambore covers several hundred square kilometres of dry deciduous forests sprawling over undulating terrain.
According to a 2009 census, there were about 40 tigers in and around the park, which is in Sawaimadhopur district of Rajasthan.
Nearly 100 villages surround the park, and the more the tiger population grows the more they are likely to come into conflict with humans, observers say.
Chief wildlife warden RN Mehrotra told the BBC the deaths of the tiger cubs could be a case of "revenge killing".
"It appears that the tigers poached a goat. The carcass of the goat was found nearby. It seems to be a case of revenge. Someone took revenge for killing their animal," he said.
Ranthambhore is a major tourist attraction, drawing about 200,000 people from India and abroad every year.