Why are ships being attacked in the Strait of Hormuz?
A container ship sank in the Strait of Hormuz in mid-October, and Iran says two more tankers hit its mines six days later. The attacks come months into a war between the US and Iran, with American warships escorting vessels through the same waters.
THE SHORT ANSWER
Because Iran's Revolutionary Guards, the country's elite armed force, say no ship may cross the strait without Iran's permission, and they are enforcing that during the war with the United States. They say vessels using a southern route near Oman are violators and that mines they laid there have set ships ablaze. The US military disputes the mine account for one sinking. Analysts say Iran also wants higher energy prices to pressure President Donald Trump before the November 3 midterm elections.
What happened
On 14 October, Singapore's maritime authority said the container ship GFS Pride had sunk in the Strait of Hormuz after being hit by an unknown projectile. All 21 crew were evacuated and no injuries were reported. Iran's Revolutionary Guards, known as the IRGC, said the ship took an "unauthorized" route and hit a naval mine. US Central Command, the American military command for the region, later said an Iranian projectile hit the ship and that it sank while being towed to shore. A second Singapore-flagged container ship, the GFS Giselle, was hit and damaged but reached a safe anchorage.
Attacks continued. On 17 October the IRGC said a super oil tanker struck a mine after turning off its positioning and radar systems. On Tuesday 20 October it said mines it had laid in the southern strait exploded under two oil tankers overnight, leaving both ablaze and unable to move. It named neither vessel and reported no casualties. It also said it had shot down a US MQ-9 drone, and it warned that oil companies would pay a bigger price if US actions continued. A UK maritime agency reported a separate Hormuz incident with no damage.
Data from that agency, as reported by an Israeli news outlet, shows Iranian forces attacked more than 20 vessels in October, one of which sank. Meanwhile the US says it has redirected 138 commercial vessels since it reinstated a naval blockade of Iranian ports on 14 July.
Why it matters
The strait is the only sea passage from the Persian Gulf to the open ocean, and it normally carries about a fifth of the world's oil. The UN's International Maritime Organization, the shipping agency, has logged 106 confirmed incidents and at least 24 seafarer deaths since the war began on 28 February. Oil and gas flows have partly recovered, but they remain below pre-war levels, and the risk to ships and crews is still rising.
- For seafarers, Crews on civilian ships carry the physical risk. At least 24 seafarers have died in confirmed incidents, and one was killed when the bulk carrier Cape Dao was hit on 23 September.
- For shipowners and insurers, Iran says mines caused the damage, while the US and Singapore point to projectiles. Our reading is that such disputes could complicate insurance and legal claims, though the reports so far do not say how.
- For Gulf energy exporters, Data provider Kpler said crude exports through the strait were at 82% of pre-war levels on 18 October. Exports of refined products such as petrol were only about 44%.
The background: a narrow chokepoint with a long record of shipping wars
A narrow waterway everyone depends on
The Strait of Hormuz lies between the Persian Gulf and the Gulf of Oman. Iran is on its north coast. On the south coast is the Musandam Peninsula, which belongs to Oman, with a small part under the United Arab Emirates. The strait is about 104 miles long and narrows to about 24 miles wide.
Several Gulf states, including Qatar, Kuwait, Bahrain, Iraq and the UAE, have no other sea route out. Onshore pipelines can carry only about 3 million barrels a day, against roughly 15 million moved through the strait by 2025. All liquefied natural gas has to go by ship.
The Tanker War, 1981 to 1988
Attacks on merchant ships in these waters are not new. During the Iran-Iraq war, Iraq began attacking commercial shipping in May 1981. Iran later hit ships belonging to Iraq's trading partners and to Gulf states that backed Iraq. Iraq carried out 283 attacks and Iran 168, and well over 100 sailors died.
The United States became involved in 1986 to protect Kuwaiti tankers. Its Operation Earnest Will ran from July 1987 to September 1988. In April 1988, after Iran mined international waters and an American warship was damaged, the US Navy struck Iranian targets in Operation Praying Mantis. In July 1988 a US cruiser shot down an Iranian airliner over the strait, killing 290 people.
Threats, seizures and mines on standby
For decades afterward, Iran threatened to close the strait without doing so for any extended time. In 2015 Iranian patrol boats fired shots across the bridge of the container ship Maersk Tigris and made it enter Iranian waters. In June 2019 two tankers were hit by explosions near the strait, and the US accused Iran, which denied it. A US-led group of countries, the International Maritime Security Construct, was formed that September to protect shipping.
A US estimate said Iran had more than 5,000 naval mines ready for fast deployment as of 2019. In June 2025 it was reported that Iranian forces loaded mines onto vessels in the Gulf. They were not deployed.
The 2026 war and the blockade
The US and Israel launched a joint attack on Iran on 28 February 2026. Before those strikes, ship insurance for the strait had already risen from 0.125% to between 0.2% and 0.4%. The Malta-flagged container ship Safeen Prestige was attacked near Oman on 4 March and later sank.
The US imposed a naval blockade of Iranian ports on 13 April and suspended it on 18 June, a day after the Islamabad Memorandum of Understanding set a temporary framework to end military operations and reopen the waterway. That framework did not hold. Washington reinstated the blockade on 14 July.
Autumn attacks and the latest sinkings
In August, Iran and Oman were reported near a deal on shipping routes, with ships entering by an Iranian-controlled lane and leaving by an Omani one, with fees attached. Instead, Iran's new maritime authority blacklisted 45 tankers on 24 August, and projectile strikes hit tankers off Oman. In September the IRGC struck a Togo-flagged tanker, and on 23 September the Cape Dao was hit. By 4 October, Iran had hit seven oil tankers in five days.
The sinking of the GFS Pride on 14 October followed, then the IRGC's mine claims on 17 and 20 October.
GOOD TO KNOW
As of 2019, a US estimate put Iran's naval mine stock at more than 5,000, ready to be laid quickly by fast boats.
Why is the southern route at the centre of the attacks?
The US Navy has escorted civilian ships along a southern route near the Omani coast for several months, trying to restore oil and gas trade. Iran generally targets tankers and cargo ships along that route. The IRGC calls it illegal and says passage needs Iran's permission.
Ships in the strait normally follow a traffic separation scheme, with one lane in and one out. Wikipedia says it lies in Omani waters, and very large vessels may need to use Iranian waters instead. The reports so far do not say whether the route the IRGC calls illegal is the same as those lanes.
Mines or projectiles: why the disagreement matters
Each side describes the same events differently. Iran says its mines hit ships that took an unauthorized route. Singapore's authority said an unknown projectile hit the GFS Pride and called the attacks "unprovoked, unjustifiable, and a breach of international law." US Central Command said an Iranian projectile struck it. The UK maritime agency said it was unclear whether two reports of the same days were linked.
Which version proves right shapes who is blamed. The reports so far do not say how the disputes will be settled.
Timeline: 1981 to today
THE TANKER WAR
Iraq begins attacking commercial ships, the start of the Tanker War in the Gulf.
Iraq widens the campaign, and Iran begins attacking tankers to and from Kuwait and other Gulf Arab states.
The US starts Operation Earnest Will to protect Kuwaiti merchant shipping.
The US attacks Iranian targets in Operation Praying Mantis after Iranian mining.
THREATS AND SEIZURES
Two tankers are rocked by explosions near the strait; the US blames Iran, which denies it.
Several countries form the International Maritime Security Construct to protect Gulf shipping.
US intelligence reportedly detects Iranian forces loading naval mines onto vessels; they are not deployed.
THE WAR AND THE BLOCKADE
The US and Israel launch a large joint attack on Iran.
The container ship Safeen Prestige is attacked near Oman and later sinks.
The US imposes a naval blockade of Iranian ports.
The Islamabad memorandum sets a temporary framework to end operations and reopen the strait.
The US reinstates the blockade after the framework fails to hold.
AUTUMN ATTACKS
Iran and Oman are reported near a deal on shipping routes, with security fees attached.
Iran's new maritime authority blacklists 45 tankers and threatens fines and seizures.
Iran and the US trade new strikes near the strait after a week of renewed fighting.
The IRGC strikes a Togo-flagged tanker, which catches fire.
The bulk carrier Cape Dao is hit by a projectile and one seafarer is killed.
Iran is reported to have hit seven oil tankers in five days.
The container ship GFS Pride sinks; Iran cites a mine, Singapore an unknown projectile.
The IRGC says mines set two tankers ablaze in the southern strait.
What to watch next
- The US midterms. The election is on November 3, and Trump has said the US would not bomb Iran before then.
- Possible renewed bombing. Iranian officials told Reuters they expect US and Israeli attacks to resume sooner or later.
- Iran's seven-day proposal. Iran would reopen the strait and resume nuclear talks in exchange for an end to the blockade, but its foreign ministry called the US response "insufficient and incomplete."
- Pakistani mediation. Pakistan's army chief, Asim Munir, a key go-between, arrived in Iran on Tuesday, though his purpose was unclear.
Sources
- Euronews20 OCT 2026
- ynetglobal20 OCT 2026
- Shafaq News..20 OCT 2026
- Yahoo News20 OCT 2026
- Mehr News Agency20 OCT 2026
- The Independent14 OCT 2026
- BBC14 OCT 2026
- ABC News14 OCT 2026
- Mehr News Agency14 OCT 2026
How this article was made: Implica's editorial system wrote it from the news reports above, with the background drawn from Wikipedia: Strait of Hormuz, Tanker war, Iran–United States relations, International Maritime Security Construct.