The chief official at the port where a Japanese tanker was docked a day after it was damaged at the mouth of the Persian Gulf said Thursday that investigators now believe the ship was involved in a collision, backing away from an earlier theory that natural causes were to blame.
But the ship's owner refused to speculate on what had set off Wednesday's incident, which it described as an explosion on the tanker, until it had more information.
The company initially said it suspected the ship had been attacked as it entered the tense Strait of Hormuz. The possibility of a deliberate attack has not been ruled out.
Captain Musa Murad, director general of the port of Fujairah, said damage to the ship's hull and interior is being investigated, but that clues point to a crash of some sort. The ship dropped anchor at the Emirati port for inspections late Wednesday.
"There was a collision. ... What it is, we don't know. That's why the investigation is going on," Murad told The Associated Press over the telephone.
Theory of a rogue swell 'not correct'
Murad was quoted by Emirati state media the previous day as saying an unusually large swell caused by a tremor damaged the ship. Other officials in the region also pointed to large waves or seismic activity in the area.
Murad dismissed those theories Thursday, saying they came from erroneous reports by local authorities before the ship had been examined in port. "It's not correct," he said.
A photo released by the Emirates state news agency WAM after the tanker arrived in Fujairah showed a large, square-shaped dent near the waterline on the rear starboard side of the ship's hull. Murad said he also saw damage to crew quarters inside the vessel, as well as some leaking water onboard.
Setsuo Ohmori, deputy chief of mission at Japan's embassy to the UAE, said "relevant people" were examining the tanker in Fujairah.
"We are waiting for the results of the investigation," he said.
'An attack from external sources'
Wednesday's incident aboard the M. Star supertanker happened shortly after midnight as the ship entered the Strait of Hormuz, heading out of the Gulf, Japanese shipping company Mitsui O.S.K. Lines said.
Mitsui said the explosion seemed to be caused by "an attack from external sources" while the tanker passed through the western part of the strategically vital waterway, a narrow chokepoint between Iran and an enclave of Oman that is surrounded by Emirati territory.
A Japanese transport ministry official in charge of crisis management declined to comment Thursday in Tokyo. The U.S. Navy's 5th Fleet, which patrols the region, said it is monitoring the situation but does not know what caused the explosion.
If the tanker was attacked, it would be a rare assault on a merchant ship in the Gulf or at the Strait of Hormuz, a transit point for about 40 percent of oil shipped by tankers worldwide.
Al-Qaida has in the past carried out attacks on oil infrastructure on land in nearby Saudi Arabia, as well as a 2002 suicide bombing against a French oil tanker off the coast of Yemen and the 2000 bombing of the USS Cole in the Yemeni port of Aden.
One of the tanker's 31 crew members noticed a flash of light right before the explosion, suggesting something may have struck the vessel. The explosion occurred at the back of the tanker, near an area where rescue boats are stored, causing cuts to a crew member who was struck with broken glass.
The Marshall Islands-flagged tanker, loaded with 270,000 tons of oil, was heading from the petroleum port of Das island in the United Arab Emirates to the Japanese port of Chiba outside Tokyo, the ministry said.
