Forest officials have registered a case and are investigating the deaths.
A leopard and its two 4-month-old cubs were found dead near a village in Karnataka's Mysore on Monday, forest officials said.
The carcasses were found Monday afternoon in Nanjanagudu's Hallare village but officials said they may have died a day before.
"There was no injury marks on their bodies but prints of struggle were seen near the spot where they were found," Karnataka Forest Department official Dr Nagraj said.
Forest officials said that the deaths could have been a result of human-animal conflict or caused by some poisonous substance. "The cause of their deaths is still to be ascertained. The postmortem report will be out by the end of this week," they said.
"The movement of the wildlife is common in these villages. Wild elephants, bison and deer snakes are often seen but leopards are rarely spotted," officials said.
Forest officials have registered a case and are investigating the deaths.