Pakistan announced a set of severe diplomatic measures against India on Thursday, accusing New Delhi of supporting cross-border terrorism, in a move that raises the stakes between the two nuclear-armed neighbors.

According to a statement from Prime Minister Shehbaz Sharif’s office, following an emergency meeting of the National Security Committee, Pakistan declared India’s naval and air defense attachés in Islamabad as persona non grata, ordering them to leave immediately.

The Pakistani government also cancelled all visas issued to Indian citizens, except for Sikh pilgrims, closed land borders, suspended trade activities, and banned Indian aircraft from its airspace.

India’s Ministry of External Affairs responded with a reciprocal move, cancelling all visas issued to Pakistani nationals after a deadly attack in the Indian-administered Kashmir region killed 26 people, mostly tourists. The Indian ban will take effect on Sunday.

The latest tit-for-tat measures have raised international concern over a possible escalation in the long-standing conflict, particularly over the disputed Kashmir region.