Investigators believe a series of attacks on oil tankers in a United Arab Emirates port were led by a foreign state – with divers on speedboats planting mines on the vessels.
Their report suggests the attacks looked like a “sophisticated and co-ordinated operation carried out by an actor with significant operational capacity, most likely a state actor”.
The US has recently accused Iran of being responsible, but the country was not named in the report.
Four tankers from the Emirates, Saudi Arabia and Norway were hit on 12 May off the Emirati coast – and it is believed limpet mines were placed below the waterline to ensure vessels were incapacitated but not sunk.
Pictures released with the report showed large holes in the hulls of the ships.
The four blasts occurred within less than an hour, suggesting the timed detonations were co-ordinated. No injuries were reported.
Early findings of a joint investigation were revealed to the UN Security Council behind closed doors on Thursday.
Scientific and naval experts using tanker debris, radar data and the precisely placed explosive charges are leading the investigation.
On Thursday, Abdallah al Mouallimi, the Saudi ambassador to the UN, said Tehran was behind the attacks.
“We believe the responsibility for this attack lies on the shoulders of Iran,” he told reporters after the briefing, echoing the assessment of US national security adviser John Bolton, who blamed Iran last week.