This 2016 photo shows the Liberian-flagged oil tanker Mercer Street off Cape Town, South Africa. The oil tanker linked to an Israeli billionaire reportedly came under attack off the coast of Oman in the Arabian Sea, authorities said Friday, as details about the incident remained few. (AP photo)

DUBAI, United Arab Emirates — An attack on an oil tanker linked to an Israeli billionaire killed two crew members off Oman in the Arabian Sea, authorities said Friday, marking the first fatalities after years of assaults targeting shipping in the region.

No one immediately claimed responsibility for the Thursday night raid on the Liberian-flagged tanker Mercer Street. However, a U.S. official said it appears a so-called suicide drone was used in the attack, raising the possibility that a government or a militia group was behind it.

The U.S. Navy rushed to the scene following the attack and was escorting the tanker to a safe harbor, a London-based ship management company said Friday.

The assault represented the worst-known maritime violence so far in regional attacks on shipping since 2019. The U.S., Israel and others have blamed the attacks on Iran amid the unraveling of Tehran’s nuclear deal with world powers. Iran now already appears poised to take an even tougher approach with the West as the country prepares to inaugurate a hard-line protege of Supreme Leader Ayatollah Ali Khamenei as president next week.

The attack Thursday night targeted the tanker just northeast of the Omani island of Masirah, over 185 miles southeast of Oman’s capital, Muscat.

London-based Zodiac Maritime, part of Israeli billionaire Eyal Ofer’s Zodiac Group, said the attack killed two crew members, one from the United Kingdom and the other from Romania. It did not name them, nor did it describe what happened in the assault. It said it believed no other crew members on board were harmed.

“At the time of the incident the vessel was in the northern Indian Ocean, traveling from Dar es Salaam to Fujairah with no cargo onboard,” the statement from Zodiac Maritime said, naming ports in Tanzania and the United Arab Emirates respectively.

Satellite tracking data from MarineTraffic.com showed the vessel had been near where British officials said the attack occurred. However, the last signal the ship sent came early Friday morning.

Zodiac Maritime described the Mercer Street’s owners as Japanese, without naming them. Shipping authority Lloyd’s List identified the vessel’s ultimate owner as Taihei Kaiun Co., which belongs to the Tokyo-based Nippon Yusen Group.

Late Friday, Zodiac Maritime said the tanker was sailing under the control of her crew “to a safe location with a U.S. naval escort.” The company did not elaborate. The U.S. Navy’s 5th Fleet, which patrols the Mideast, did not respond to a request for comment.

British military’s United Kingdom Maritime Trade Operations said an investigation was underway into the attack and that coalition forces were taking part.

A U.S. official, speaking on condition of anonymity to discuss the ongoing investigation, told The Associated Press that the attack appeared to have been carried out by a “one-way” drone and other drones took part. The official said it wasn’t immediately known who launched the attack and declined to elaborate.

The official’s remark came after an earlier report from private maritime intelligence firm Dryad Global referred to a drone sighting involving the vessel prior to the attack. Iran and Yemen’s Tehran-backed Houthi rebels have employed suicide drones in the past, unmanned aircraft loaded with explosives that detonate on impact with a target.