Investigators have found traces of explosive on a Japanese supertanker damaged near the Strait of Hormuz last week and conclude the ship was the target of an attack, the United Arab Emirates news agency said on Friday.
The 31 crew aboard the 333-metre-long M.Star reported an explosion shortly after midnight on July 28, injuring one seaman but causing no oil spill or disruption to shipping in the strategic waterway.
"An examination carried out by specialised teams has confirmed that the tanker has been the subject of a terrorist attack," the state news agency WAM said, quoting an unidentified coastguard source.
"UAE explosives experts who collected and examined samples found a dent on the starboard side above the water line and remains of home-made explosives on the hull", the source said.
A spokeswoman for shipowner Mitsui O.S.K. said the company could not confirm details of the WAM report.
"The investigation on the tanker is still continuing, and while we are looking at all possibilities, the company has not heard anything that will help determine the cause of the damage," she said.
A spokesman for the U.S. Fifth Fleet, part of an international coalition of navies that patrol Gulf waters, confirmed U.S. Navy divers had played a part in investigations but had no immediate comment on the UAE report.
The report said the M.Star had left UAE waters to resume its voyage to Japan and trade sources confirmed the ship's departure.
Industry sources said the tanker carried more than 2 million barrels of Qatar Land and Abu Dhabi Lower Zakum crudes, equivalent to about half of Japan's daily oil needs.
The M.Star incident provoked several theories about the cause, ranging from a freak wave to a collision with a U.S. nuclear submarine.
Two days ago, a statement from a group calling itself the Abdullah Azzam Brigades claimed responsibility for the incident.
Bordered by Iran, Oman and the United Arab Emirates, the narrow Strait of Hormuz handles 40 percent of the world's seaborne oil and is patrolled by U.S. and other warships.
A Japanese Foreign Ministry official had no immediate comment on the report.
Mitsui President Koichi Muto said he did not rule out the possibility that an attack caused damage to the ship, the Nikkei business daily said on Friday. The ship was smashed in on the starboard side of its hull above the water line and a lifeboat was blown off the deck and windows and doors were smashed.
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