By The South Asia Times

NEW DELHI — In a dramatic escalation that has pushed India-Iran relations to a breaking point, Iranian naval forces fired upon two Indian-flagged oil tankers in the Strait of Hormuz on Saturday, forcing them to turn back just hours after Tehran had declared the vital waterway "completely open."

The attack -- which shattered the window of one vessel and sent crews into a desperate panic -- has triggered a formal diplomatic protest from New Delhi, which summoned Iranian Ambassador Mohammad Fathali to convey "deep concern" over the incident.

The two targeted vessels -- the VLCC Sanmar Herald, carrying nearly 2 million barrels of Iraqi crude, and the bulk carrier Jag Arnav -- had been given prior clearance to transit the strait. But as they approached the chokepoint, Iranian Revolutionary Guard Corps (IRGC) reportedly gunboats opened fire without warning.

A distress call captured on maritime channels revealed the confusion and terror aboard the Sanmar Herald:

 

"Sepah Navy! Motor Tanker Sanmar Herald! You gave me clearance to go... My name is second on your list. You are firing now! Let me turn back!" 

Indian officials confirmed that a window pane on one of the vessels was shattered by gunfire, though no crew casualties were reported. Both ships reversed course and returned to the Persian Gulf.

The attack was part of a broader Iranian crackdown on Saturday. According to official sources, a convoy of 14 India-bound ships -- carrying crude oil, LPG, and fertilizers -- was stopped by the IRGC as they attempted to transit the strait. Thirteen were forced to turn back or remain anchored near Larak Island, waiting for clearance that never came.

Only one Indian-flagged vessel, the oil tanker Desh Garima, successfully crossed and is now heading toward India.

Iran's navy broadcast a radio message declaring the strait "completely closed again," citing the "failure of the US government to fulfill its commitment in the negotiation". The IRGC further warned: "Approaching the Strait of Hormuz will be considered cooperation with the enemy, and the offending vessel will be targeted".

In New Delhi, Foreign Secretary Vikram Misri summoned Iranian Ambassador Mohammad Fathali on Saturday evening, lodging a formal protest and urging Tehran to "resume at the earliest the process of facilitating India-bound ships across the Strait".

Saturday's attack cannot be understood without reference to a far deeper wound in India-Iran ties -- one that has left Tehran seething with suspicion toward New Delhi.

On March 4, 2026, a US Navy submarine torpedoed and sank the Iranian frigate IRIS Dena in international waters approximately 20 nautical miles off the southern coast of Sri Lanka. At least 87 Iranian sailors were killed.

The Dena was returning from MILAN 2026, a multinational naval exercise hosted by the Indian military. It had been a guest of the Indian Navy.

For Tehran, the optics were devastating: an invited guest warship, sailing home after participating in India's premier naval exercise, was hunted and destroyed -- and New Delhi's response was muted.

Indian Foreign Minister S. Jaishankar described the sinking as part of the "reality of the Indian Ocean," adding that the Iranian crew "got caught on the wrong side of events".

Opposition leader Rahul Gandhi accused Prime Minister Narendra Modi of having "surrendered our strategic autonomy" and maintaining a "compromised" silence. 

But behind the scenes, Iranian officials are believed to harbor deep resentment. In their view, India knew -- or should have known -- that US submarines were operating in the area. Some Iranian strategists have questioned why New Delhi did not warn the Dena or provide an escort, and why India has not condemned the attack publicly.

Saturday's firing on Indian tankers may be read in Tehran as a message: You did not protect our sailors when they were your guests. Do not expect us to protect your oil ships now.