Tensions between South Asia’s two nuclear-armed neighbours have surged following a deadly exchange of drone and missile attacks, with both India and Pakistan claiming to have repelled cross-border assaults while accusing each other of unprovoked aggression.

Pakistan’s military announced on Wednesday that it had downed 25 Indian drones in various regions along the eastern border, asserting the attacks were deliberate violations of its airspace.

The military described the operation as a "firm and calibrated response" to protect Pakistan’s sovereignty.

Meanwhile, India reported thwarting a coordinated Pakistani drone and missile strike targeting one of its key military installations in the northern region.

Indian defence officials said the attempted incursion was “aggressively neutralised,” preventing any major damage or casualties.

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The flare-up follows a deadly Indian offensive on Tuesday that reportedly killed at least 31 people and injured dozens more in Pakistan’s Punjab province and parts of Pakistan-administered Kashmir. Islamabad has condemned the attack as an "act of brutality."

Speaking at an emergency press briefing, Pakistani Prime Minister Shehbaz Sharif vowed retaliation. “We will avenge the blood of our innocent martyrs,” he declared. “India’s unprovoked aggression will not go unanswered.”

India, however, maintains that its actions were in response to “continued infiltration attempts and militant threats emanating from Pakistani territory.”

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The cross-border hostilities have prompted international concern, with calls from the United Nations and regional partners urging both nations to exercise restraint and avoid further escalation.

As of Thursday morning, military activity was reported to be ongoing in some border areas, with residents in both countries fearing a deeper conflict may be imminent.

Source: With inputs from Al Jazeera