Shipping officials said Thursday that they were examining the hull of a Japanese oil tanker that was mysteriously damaged this week as it traversed a strategically vital waterway between Iran and the Arabian Peninsula. The ship’s owner has said that it may have been attacked.
With the tanker docked in the United Arab Emirates, the owner, Mitsui O.S.K. Lines, and port officials puzzled over what had shattered windows on the vessel, knocked off a lifeboat and punched a dent into its hull. The damage was apparently inflicted early Wednesday morning in the Strait of Hormuz, a passageway for shipping much of the world’s oil from the Middle East.
Mitsui officials said that crew members on the ship, the M. Star, had seen a flash and heard an explosion. They also dismissed earlier speculation by officials in Iran and Oman that the damage had been caused by a “freak wave.”
“We have not reached a conclusion, but we still suspect the tanker was hit by a blast,” Masahiko Hibino, a safety official with the shipping line, said at a news conference in Tokyo, according to Agence France-Presse.
The shipping company told reporters it was continuing to investigate, with help from Britain’s Maritime Trade Operations and the United States Navy. This spring, the United States and other countries aided South Korea’s investigation into an explosion that sank one of its warships, with the inquiry ultimately placing blame on a North Korean torpedo.
American military officials were dubious of Mitsui’s contention that the tanker had been attacked, saying that the photographs showed that damage more consistent with a collision of some kind, perhaps with a dock or another ship. But the Mitsui officials reported no collisions.
Most officials dismissed the idea of a collision with a submarine, because no damaged sub is known to have surfaced. American officials reported no collision with United States submarines in the region.
One crew member aboard the Japanese tanker was slightly injured when the ship was damaged, but the ship’s owner said no oil had leaked from the damaged hull. The company said the tanker had loaded up with about two million barrels of crude oil in the United Arab Emirates on Tuesday and had been heading for Japan.
The company released photographs on Thursday showing a large, square dent in the black-and-red hull of the tanker and broken railings along its deck, damage that appears unlikely to have been caused by a wave. Photos of the interior show broken ceiling panels and exposed insulation and wiring in one of the dining rooms.
Theodore Karasik, a Dubai-based security analyst, said that the leading theory there was that an old mine was adrift and bumped the ship; if it had degraded, it could have simply produced a pressure blast. There are still mines in the region from the Iran-Iraq war of the 1980s. Another possibility, he said, was a collision with another ship.
Moosa Murad, general manager of the Port of Fujairah, where the tanker docked on Wednesday, told Reuters that he suspected that the ship had been involved in a collision, perhaps with a submarine or sea mine, but added, “We don’t know what it was.”
It would not be the first collision in the narrow Strait of Hormuz, a link between the Persian Gulf and the Arabian Sea. In March 2009, a United States Navy nuclear-powered submarine and a Navy warship crashed, damaging both ships and injuring 15 crew members on the submarine. And in January 2007, another Navy submarine collided with a Japanese oil tanker, causing light damage to the Japanese ship.
But Lt. John Fage of the United States Navy’s Fifth Fleet, based in Bahrain, said questions were still swirling about what had damaged the M. Star.
“That’s been the question of the day,” he said. “Do we know what caused this? And the answer is no.”
