SRINAGAR, India, April 24, (AP): Tensions between arch rivals India and Pakistan were high on Thursday as New Delhi mounted a diplomatic offensive against Islamabad, blaming it for a deadly attack that killed 26 people, mostly tourists, in disputed Kashmir. India accused Islamabad of supporting "cross-border terrorism” Wednesday night and imposed diplomatic measures, including downgrading diplomatic ties, suspending of a key water-sharing treaty and closing the main land border crossing with Pakistan.

Pakistan has denied the accusation and a previously unknown militant group calling itself Kashmir Resistance has claimed responsibility for the attack. Islamabad said it would respond to India’s actions on Thursday and convene its National Security Committee, which is composed of senior civil and military officials. "India has taken irresponsible steps and leveled allegations,” Pakistan’s Foreign Minister Ishaq Dar told local Dunya News TV channel.

Dar said India’s steps had so far been "non-kinetic,” and added that "any kinetic step by India will see a tit-to-tat kinetic response” from Pakistan. Diplomatic ties between the two countries were already weak, particularly after New Delhi after India revoked Kashmir's semiautonomous status in 2019. India and Pakistan each administer a part of Kashmir, but both claim the territory in its entirety.

The two sides have long accused each other of backing forces to destabilize one another, and New Delhi describes all militancy in Kashmir as Pakistan-backed terrorism. Pakistan denies this, and many Muslim Kashmiris consider the militants to be part of a home-grown freedom struggle. India said a number of Pakistani diplomats were asked to leave New Delhi and Indian diplomats were recalled from Pakistan.

Diplomatic missions in both countries will reduce their staff from 55 to 30 as of May 1, India’s foreign secretary, Vikram Misri, announced Wednesday night. Misri also said the only functional land border crossing between the countries would be closed, adding that India was also suspending a landmark water-sharing treaty. The Indus Water Treaty, brokered by the World Bank in 1960, allows for sharing the waters of a river system that is a lifeline for both countries, particularly for Pakistan’s agriculture. The treaty has survived two wars between the countries, in 1965 and 1971, and a major border skirmish in 1999.