Tanker carrying 27 Indians hit by limpet mines in Hormuz, what are these explosives?

A Panama-flagged crude oil tanker carrying 27 Indian seafarers was targeted with limpet mines in the Strait of Hormuz, triggering a fire onboard. All Indian crew members aboard MT Louise 1 escaped without injuries, Union Shipping Minister Sarbananda Sonowal confirmed.

In a post on X, Sonowal said the Indian seafarers were “completely safe with no injuries”. The incident took place on Thursday, around 25 nautical miles (46 km) northeast of Khasab in Oman, according to the British maritime monitoring agency United Kingdom Maritime Trade Operations (UKMTO). The identity of those behind the attack remains unknown.

The incident comes amid mounting threats to commercial shipping in the strategically important waterway, which is a major route for global energy supplies.

Small boat reportedly attached explosives to tanker

According to three maritime sources cited by Reuters, a small boat approached MT Louise 1 and attached two limpet mines to its hull. The explosives caused a fire and temporarily disabled the vessel.

The attack marks the first reported successful use of such explosives in the Strait of Hormuz since the US-Iran conflict began. Two maritime sources also told Reuters that an earlier attempt to use similar devices in September had failed, as the explosives did not detonate.

In a separate incident, Sonowal said a Liberia-flagged tanker, VLCC MT Arzanah, was also hit by a projectile. Two Indian nationals aboard the vessel were reported to be safe.

Iran claims four tankers caught fire

Iran's Revolutionary Guards Navy said on Friday that four oil tankers had caught fire and exploded in the Strait of Hormuz while attempting to navigate routes it described as unauthorised. According to a Reuters report, the IRGC also claimed that one tanker carrying 2 million barrels of crude oil had struck a naval mine.

The attacks come against the backdrop of the ongoing West Asia conflict, which began with US-Israeli strikes on Iran in February. Tehran subsequently retaliated with attacks on US interests and military bases in Gulf countries, while effectively restricting navigation through the Strait of Hormuz.

Iran has targeted vessels it accuses of violating its passage restrictions, while the US Central Command has struck and disabled Iranian and Iran-linked tankers amid Washington's naval blockade of Tehran.

What are limpet mines?

Limpet mines are naval explosives attached directly to a ship's hull using magnets or clamps. Originally developed by British special forces during World War II, these devices are designed for sabotage operations.

Greece-based maritime risk management firm Marisks said the explosives were first deployed in West Asia in 2017 and subsequently used against tankers in the Strait of Hormuz.

Explaining their continued use, the group said they “are cheap and easily available”.

“The methodology of a small craft attaching these mines on the hulls of vessels in transit is cheap, low tech and very efficient,” Marisks added.