India's Prime Minister Narendra Modi says the gunmen behind a terrorist attack on tourists in the Kashmir region "will not be spared!"

Twenty-six men were killed and 17 were injured when suspected militants opened fire at tourists in India's Jammu and Kashmir territory, police said.

Relations between India and Pakistan are cratering following a deadly attack in the disputed Himalayan region of Jammu and Kashmir that left more than two dozen tourists dead, raising fears of military escalation between the nuclear-armed rivals.