SRINAGAR, India — India blamed Pakistan on Wednesday for a militant attack that killed 26 people in Indian-held Kashmir, downgrading diplomatic ties and suspending a crucial water-sharing treaty that has withstood two wars between the nuclear-armed rivals.

India's External Affairs Ministry said the Indus Water Treaty will be suspended after an attack in Kashmir left over two dozen dead.

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.