Skip to content 
On Oct. 5, a week of heightened violence around the Strait of Hormuz came to a close. According to three maritime security sources, at least 12 attacks hit tankers during the seven days from Sept. 28. They said it was the most in any single week since the U.S. war with Iran began on Feb. 28.
What the data show
The sources analyzed incidents using information received from the area. The targets were tankers carrying oil, liquefied natural gas (LNG) and liquefied petroleum gas (LPG).
The International Maritime Organization (IMO), the UN shipping agency, logged nine incidents involving vessels in the same week. Maritime sources said the IMO usually takes longer to verify and officially record events, which may explain the gap.
- At least 12: tanker attacks, Sept. 28 to Oct. 5, per security sources.
- Nine: incidents recorded by the IMO for the same week.
- Eight: incidents in the week of July 13, the closest comparable week in IMO data.
Harassment continues
The U.S. Navy-led Joint Maritime Information Centre (JMIC) reported in a Sunday note that attacks, attempted attacks and harassment persisted. Activity included drone overflights, surveillance and VHF radio hailing by Iran’s Revolutionary Guards. The JMIC said the actions showed Iran’s intent “to assert presence along key transit lanes and maintain pressure on transiting vessels.”
India’s foreign ministry said that 12 crew were hurt when an unknown projectile struck the Panama-flagged tanker On Peace as it passed through the strait.
Export flows
The attacks came as Persian Gulf producers pushed exports higher. Shipping data released Monday showed Gulf oil exports above pre-war volumes for roughly half of September. The report added that continued tanker attacks and operational limits make it uncertain whether those higher volumes can last.
What it means for shippers
The source covers tankers, not container lines, so direct effects on boxed cargo are not described. Still, the facts point to several practical steps.
Shippers with exposure to Gulf energy, petrochemical or gas-linked inputs should ask suppliers and carriers about sailing schedules and routing. Volatile flows can affect fuel-linked surcharges, so review how bunker and fuel adjustments are calculated in your quotes. Confirm insurance terms for cargo moving near the region, and check whether cover has changed.
Our earlier coverage tracked how the disruption developed. See the report on Hormuz traffic falling to 5% of normal, the update on the long effective closure and paused talks, and the note on Maersk’s detention relief at Gulf-area ports.
For cost planning, our guide on reducing international shipping costs and spot rate exposure covers general steps. Build in extra lead time for any cargo tied to the region, and keep documents ready in case routing changes late.
