Hormuz Tanker Attacks Reach Weekly High Since Iran War Began

LONDON (Reuters) - Attacks on tankers sailing through the Strait of Hormuz reached their highest weekly level since the Iran war began, according to maritime security sources tracking incidents, amid a bigger export push by Gulf producers.

Attacks, attempted attacks and harassment activity including drone overflights, surveillance and hailing using VHF radio by Iran's Revolutionary Guards have persisted in the strait, the US Navy-led Joint Maritime Information Center (JMIC) said in a note on Sunday 4 October 2026. 

"These actions continue to demonstrate Iran’s intent to assert presence along key transit lanes and maintain pressure on transiting vessels," the JMIC said. 

Between Monday 28 September and Monday 5 October 2026, there had been at least twelve attacks on oil, liquefied natural gas and liquefied petroleum gas tankers around the Strait of Hormuz, according to data from three maritime security sources who analysed incidents based on information received from the area.

That was the highest number of attacks in a single week since the US war with Iran began on 28 February 2026, the sources said.

Separate data collated by the UN's shipping agency, the International Maritime Organization (IMO), showed nine incidents involving vessels in the same week. 

The UN body tends to take longer to verify and officially record incidents, maritime sources say. 

The closest week in terms of comparable incidents was the week of 13 July 2026 when there were eight incidents, separate IMO data showed. 

Gulf oil exporters topped pre-war levels for about half of September, shipping data showed on Monday 5 October 2026, though attacks on tankers and logistical constraints cloud the outlook for sustained higher flows.

India's foreign ministry said on Tuesday 6 October 2026 that twelve crew members were injured after an unknown projectile struck Panama-flagged oil tanker On Peace while it was passing through the Strait of Hormuz.