At least 16 Indian soldiers were killed on Friday when their vehicle skidded off the road in the mountainous north-eastern state of Sikkim.
Four soldiers were injured in the accident in the Zema area of Sikkim, the Indian Army said.
“The accident happened when the vehicle skidded down a steep slope while negotiating a sharp turn,” the army statement said.
The injured were taken to the nearest hospital, authorities said, with no updates on their condition provided immediately.
Sikkim is bordered by Bhutan, Nepal and China and is a strategic region for New Delhi.
India is developing its military and civilian infrastructure in the remote state to match rival China in the middle of a dispute over the undemarcated border between the two nations.
New Delhi last week accused Beijing of attempting to change the status quo on the border, saying People's Liberation Army troops had entered its territory in Arunachal Pradesh.
The Indian Army said at least six of its soldiers were injured when the rival troops clashed. Injuries on the Chinese side are not known.