Explosive-laden Iranian boats appear to have attacked two fuel tankers in Iraqi waters, setting them ablaze and killing one crew member on Wednesday, after projectiles struck four vessels in Gulf waters, said port, maritime security and risk firms.

The latest attacks on ships linked to the US and Europe mark an escalation in the conflict between Iran and US-Israeli forces, raising the number of ships struck in the region since fighting began to at least 16.

Shipping in the Gulf and along the narrow Strait of Hormuz, which carries around a fifth of the world’s oil, has come to a near-standstill since the US and Israel began strikes on Iran on February 28, sending global oil prices surging to highs not seen since 2022.

Iran’s Revolutionary Guards have said that if attacks on Iran continued, they would not allow “one litre of oil” to be shipped from the Middle East to the US, Israel or their partners.

Trump warned Washington would strike Iran harder if it blocked oil exports, and said oil companies should use the strait because “just about all of (Iran’s) navy is gone.”

The vessels targeted in Wednesday’s late-night attacks in the Gulf near Iraq were the Marshall Islands-flagged Safesea Vishnu and the Malta-flagged Zefyros, which had loaded fuel cargoes in Iraq, two Iraqi port officials said.

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Iraq’s State Organization for Marketing of Oil (SOMO) said the Safesea Vishnu was chartered by an Iraqi company contracted with SOMO, and that Zefyros was loaded with condensate products from Basra Gas Company. Both were attacked in the ship-to-ship loading area within Iraqi territorial waters, SOMO said.

Iraqi oil ports closed

Iraq’s oil ports have completely stopped operations following the assaults, while commercial ports continue to function, Iraq’s state news agency said, citing the head of the state-run General Company for Ports of Iraq (GCPI).

The United Kingdom Maritime Trade Operations (UKMTO) said the crew of one ship had been evacuated and were reported safe.

“A boat belonging to the Iraqi Ports Company rescued 25 crew members from the two vessels, and the fires are still burning on both ships,” Farhan al-Fartousi, GCPI’s director general, told Reuters.

Iraqi rescue teams continue searching for other seafarers.

“We recovered the body of a foreign crew member from the water,” one port security official said.

The Safesea Vishnu’s commercial operator and beneficial operator are Safesea Transport Group and Safesea Group, respectively, according to data from Lloyd’s List Intelligence.

Those US-based companies did not immediately respond to requests for comment.

One Iraqi port security source said Zefyros is flagged in Malta and provided Reuters with a list of crew names.

Lloyd’s List Intelligence data showed UK-based Cygnus Tankers Limited as the commercial operator and the George & Vassilis Michael family group of companies, a key player in Greek shipping, as the beneficial owner of a tanker matching that name and flag registry.

Cygnus Tankers did not immediately respond to requests for comment. Reuters was not able to immediately reach the beneficial owner.

Revolutionary Guards vow to target ships

Iran’s Revolutionary Guards have repeatedly warned that any ship passing through the Strait of Hormuz will be targeted.

Two projectiles of unknown origin struck the Thai-flagged Mayuree Naree dry bulk vessel as it sailed through the strait earlier on Wednesday, causing a fire and damaging the engine room, the ship’s Thai-listed operator Precious Shipping PSL.BK said in a statement.

“Three crew members are reported missing and believed to be trapped in the engine room,” Precious Shipping said.

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“The company is working with the relevant authorities to rescue these three missing crew members,” it said, adding that the remaining 20 crew members had been safely evacuated and were ashore in Oman.

Images provided by the Thai navy showed smoke pouring out of the back of the ship.

Iran’s Guards said in a statement carried by the Tasnim news agency that the ship was “fired upon by Iranian fighters”, suggesting the first direct engagement by the Guards who have previously fired missiles or drones.

The US Navy has refused near-daily requests from the shipping industry for military escorts through the Strait of Hormuz since the start of the war on Iran, saying the risk of attacks is too high for now, sources familiar with the matter told Reuters.

Trump has said the US is prepared to provide naval escorts whenever needed.

Three other ships sustain minor damage

The Japan-flagged container ship ONE Majesty also sustained minor damage on Wednesday from an unknown projectile 25 nautical miles (46 km) northwest of Ras Al Khaimah in the United Arab Emirates, two maritime security firms said.

Its Japanese owner Mitsui O.S.K. Lines 9104.T and a spokesperson for Ocean Network Express, its charterer, said the vessel was struck while at anchor in the Gulf and an inspection of the hull revealed minor damage above the waterline.

All crew are safe, they said, adding that the vessel remains fully operational and seaworthy. The owner said the cause of the incident remained unclear and was under investigation.

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A third vessel, a bulk carrier, was also hit by an unknown projectile approximately 50 nautical miles (92.6 km) northwest of Dubai, maritime security firms said.

The projectile had damaged the hull of the Marshall Islands-flagged Star Gwyneth, maritime risk management company Vanguard said, adding that the vessel’s crew were safe. Owner Star Bulk Carriers SBLK.O said the ship was hit in the hold area whilst anchored. There were no crew injuries and no listing.

Early on Thursday, UKMTO said an unidentified projectile struck a container ship, causing a small fire, 35 nautical miles north of Jebel Ali in the UAE. The crew were reported safe.

The Guards’ statement included a reference to another ship, which it said was hit by projectiles – usually a reference to drones – on Wednesday morning. Reuters was not immediately able to confirm that report.