134 maritime incidents and 25 seafarer deaths on IMO tally
Key Facts
The International Maritime Organization recorded 134 confirmed incidents and 25 confirmed seafarer deaths on its Strait of Hormuz and Middle East incident dashboard, according to its November 11, 2026 update. The tally covers the wider region and is not limited to the Strait of Hormuz alone. The figures come as attacks on ships continue, while environmental estimates point to a wider detection of oil slicks in the Gulf and surrounding waters. The IMO secretary-general said the agency’s technical and operational regulations “were put in place to protect seafarers, ships and the marine environment, and must be respected and effectively enforced.” The figures distinguish incidents and deaths recorded by the IMO from spill estimates reported by Greenpeace.
Greenpeace said it had detected more than 500 oil spill events by satellite since February 28, distributed across the Gulf, the Strait of Hormuz and the Arabian Sea, according to The Guardian. The total does not mean all the slicks resulted from strikes on ships; the findings include major spills linked to attacks and others that appeared around the time of strikes but whose source could not be confirmed. Nina Noel of Greenpeace estimated the cumulative area of daily slicks at about 20,000 square kilometers. That figure combines the areas detected each day and does not describe a single slick covering that area at one time. The findings point to environmental effects extending beyond the site of any single incident, according to the report, while the origin of some spills remains unresolved.
The background to the figures includes more than 133 attacks on oil tankers since the start of the conflict, The Guardian reported, citing Greenpeace. The Washington Institute for Near East Policy said October was the worst month, with more than 30 confirmed or reported attacks in the strait and surrounding waters. Among the incidents described by Greenpeace was an attack on the supertanker JIM 2 off the coast of the United Arab Emirates in October, which left a slick stretching more than 21 miles, or 35 kilometers. The UAE closed beaches, launched a cleanup operation and monitored desalination plants after the attack. On October 30, authorities said the spill had stopped and pollution was receding.
The IMO’s Marine Environment Protection Committee warned in May that attacks could cause widespread pollution at sea, including oil, hazardous and noxious substances, missile and drone debris, fires and explosions. The committee asked the secretary-general to monitor the environmental effects and report to the next session of the IMO Council. Amid disruption to shipping, UNCTAD said daily ship transits through Hormuz fell from about 130 in February to 6 in March, a decline of about 95%. The IMO said thousands of seafarers, port workers and offshore crews had been affected by the situation in the region. It also said the voluntary evacuation mechanism for commercial ships stranded inside the Gulf region is currently suspended.
In a later development on November 12, Iran’s military said four oil tankers had been hit by explosions in the Strait of Hormuz, Reuters reported, adding that it could not immediately verify the account. Reuters also reported that at least 10 ships were hit during the first 10 days of November, following 37 attacks in October, citing data from the Washington Institute for Near East Policy. The incidents place tanker traffic among the continuing security risks in the corridor, while some details of the attacks remain attributed to their sources. The IMO tally combines confirmed incidents across the region, while Greenpeace’s data map the scope of environmental monitoring and show that the origin of some slicks has not been determined. The IMO is due to monitor the environmental effects and report them to its Council at its next session.