Assam forest minister Rokybul Hussain said the north-eastern state received permission from the federal government to amend the 1972 Wildlife Protection Act to introduce a more stringent punishment for poachers.
Mr Hussain said the enhanced punishment came into law in the state two days ago.
Belinda Wright of the Wildlife Protection Society of India said that in the rest of the country, the Act permits prison terms of three to seven years for killing wild animals.