At least 20 Indian soldiers were killed in a clash with Chinese forces in a disputed Himalayan border area, Indian officials say.

The incident follows rising tensions, and is the first deadly clash in the border area in at least 45 years.

The Indian army initially said three of its soldiers had been killed, adding that both sides suffered casualties. But later officials said a number of critically injured soldiers had died of their wounds.

India’s external affairs ministry accused China of breaking an agreement struck the previous week to respect the Line of Actual Control in the Galwan Valley.