The elephants, including five calves, were found dead during the rains in the Kondali Protected Forest Reserve, said Jayanta Goswami, head of wildlife. The ranger reached the remote area on Thursday and found 14 elephants dead on top of a hill and four at its bottom. Preliminary reports from vets say the elephants were struck by lightning, but Goswami said autopsies were underway to determine the exact cause of death.
The reserve is located in Nagaon District, Assam State, 150 kilometers east of Gauhati, the state capital.
Assam is home to around 6,000 or more wild Asian elephants that constantly come out of the forests in search of food.
Environmentalists have urged the government to prevent encroachment of populations and establish free corridors for elephants to move between forests safely. In recent years, wild elephants have entered villages, destroyed crops and even killed people.