The collision between Indian and Pakistani naval vessels in the North Arabian Sea on 15 September 2026 has become the latest flashpoint in maritime tensions between the two countries.

The incident involved INS Kolkata, a Project 15A Kolkata-class guided missile destroyer of the Indian Navy, and PNS Hunain, an OPV 2600-class offshore patrol vessel of the Pakistan Navy.

According to India, the Pakistani ship executed a dangerous overtaking manoeuvre at high speed, resulting in the collision. Pakistan has rejected this account, alleging instead that the Indian warship carried out a provocative manoeuvre.

INS Kolkata is a 164-metre-long guided missile destroyer built by Mazagon Dock Shipbuilders in Mumbai. It has a full-load displacement of about 7,400 tons and can sail at speeds of up to 30 knots. 

Commissioned in August 2014, it is designed as a high-end surface combatant with long-range air-defence, anti-surface, and anti-submarine capabilities. The vessel is equipped to operate helicopters and carries the BrahMos supersonic cruise missile as its principal strike weapon.

PNS Hunain, designated F-273, is a 98-metre-long offshore patrol vessel built by Damen Shipyards in Romania and commissioned in July 2024. With a displacement of about 2,600 tons and a top speed of 24 knots, it is part of Pakistan’s OPV 2600 series, a follow-on to the Yarmook-class patrol ships. 

Pakistan describes Hunain as a multi-purpose platform capable of maritime surveillance, patrol, and security missions, equipped with electronic-warfare systems, anti-ship and anti-air warfare capabilities, and terminal defence systems. It can also embark a multirole helicopter.

India’s Ministry of External Affairs stated that INS Kolkata was conducting routine surveillance when PNS Hunain approached at high speed and manoeuvred dangerously close. On 18 September, India rejected Pakistan’s diplomatic response and reiterated that the Pakistani vessel’s actions violated both the 1991 bilateral agreement and the International Regulations for Preventing Collisions at Sea. India emphasised that INS Kolkata suffered no major damage and remains deployed at sea.

Pakistan, however, has maintained that the Indian warship carried out a provocative manoeuvre during the encounter. The precise sequence of movements immediately before the collision remains disputed. Pakistan has claimed that Hunain sustained damage and returned to harbour following the incident.

The 1991 Agreement between India and Pakistan on Advance Notice on Military Exercises, Manoeuvres and Troop Movements includes Article 10, which specifically addresses maritime safety.

It stipulates that naval ships and submarines of the two countries should not approach within three nautical miles of each other while operating in international waters, in order to avoid accidents. This provision, equivalent to about 5.6 kilometres, is a bilateral confidence-building measure rather than a universal maritime rule.

This is not the first time such an incident has occurred. In June 2011, Pakistani warship PNS Babur came dangerously close to Indian Navy frigate INS Godavari during anti-piracy operations in the Gulf of Aden, causing minor damage. India lodged a protest at the time, citing navigational safety violations under the same framework.

Following the latest collision, India summoned Pakistan’s Chargé d’Affaires in New Delhi and lodged a strong protest. Simultaneously, India’s Charge d’Affaires in Islamabad was instructed to raise the matter with Pakistan’s Foreign Ministry.

New Delhi has advised Pakistan to ensure that its military units exercise due care and comply with relevant bilateral agreements to prevent recurrence. India has stressed that the fact the collision occurred in international waters does not exempt the two navies from adhering to agreed rules of conduct.

The unresolved question remains the exact sequence of manoeuvres that brought the two vessels into close proximity. Analysts note that while INS Kolkata continues to operate at sea, the incident underscores the fragility of maritime interactions between India and Pakistan, where even routine deployments can escalate into diplomatic confrontations.

Agencies