Indian media sources reported that 20 soldiers had been killed by a large Chinese "Death Squad" consisting of 300 troops in a hand-to-hand clash in the Ladakh region Monday.
The fighting took place after China claimed Indian troops crossed the contended border area. According to reports, firearms were not used.
Indian PM Modi said: "India wants peace but when provoked, [it] is capable of giving a fitting reply, be it any kind of situation."
He said India would be "proud that our soldiers who died fighting the Chinese."
The two states held talks following the incident to defuse tensions.