DUBAI — An explosives-laden boat carried out a "terrorist attack" that damaged a Japanese oil tanker in the Strait of Hormuz last week, the United Arab Emirates said on Friday, raising security fears for the vital waterway.
"The investigation and examination conducted by special teams have shown the tanker was attacked with explosives, prepared using traditional methods, which were loaded on a boat that approached the ship," a UAE coastguard spokesman said on the official WAM news agency.
"UAE explosives experts… found a dent on the starboard side above the water line and remains of home-made explosives on the hull," when they inspected the ship off the UAE port of Fujairah, the official said.
"Probably the tanker had encountered a terrorist attack from a boat loaded with explosives," he was quoted as saying on the agency's English-language website.
In Tokyo, Japanese Transport Minister Seiji Maehara said he had instructed ministry officials to ask the UAE authorities for details of the investigation, as requested by the prime minister.
"Without prejudgment, we will carry out our analysis on the cause of the incident," Maehara was quoted as saying by Jiji Press.
Japan "should take a firm stance" in response to such incidents because they threaten the country's oil imports, the minister added.
The world's second largest economy sources some 90 percent of its oil from the Middle East, much of it from the Gulf, where the tanker was sailing from.
Jihadists on Tuesday claimed a suicide bomber had struck the ship owned by Mitsui OSK Lines, which reported that tanker the M Star appeared to have been hit by a blast on July 28 in international waters between Iran and Oman.
US monitoring group SITE Intelligence said the Brigades of Abdullah Azzam claimed in a message on jihadist websites that it had placed a suicide bomber on the tanker, identifying him as Ayyub al-Taishan.
The little-known group with links to Al-Qaeda last October claimed responsibility for a rocket salvo into northern Israel from Lebanon, as well as for bombings in Egypt's Red Sea resort of Sharm el-Sheikh and two other resorts in 2004 that killed a total of 98 people.
It said the attack on the tanker was carried out in the name of Omar Abdul Rahman, the Egyptian "Blind Sheikh" imprisoned in the United States for his role in the 1993 World Trade Center bombing in New York.
The tanker attack sought "to weaken the infidel global order which is thrust unto Muslim lands and which loots its resources," the group said, according to SITE.
The militants said that because of the potential effect of this attack on oil prices and the global economy, "the enemies of Allah concealed the reality of the operation."
Mitsui OSK maintained the damage was caused in an attack despite reports that it had been caused by a freak wave.
The Japanese shipping firm said crew members saw a flash and heard an explosion shortly after midnight.
One crewman was slightly wounded in the blast, which caused minor damage to the vessel, including an indentation several metres (yards) across its hull, according to pictures published by WAM.
The Japan-bound vessel — crewed by 16 Filipinos and 15 Indians — was carrying 270,000 tonnes of crude oil from the Gulf but did not suffer a spill.
It arrived under its own steam to Fujairah for repairs, where an investigation into the incident was launched.
The UAE coastguard spokesman said the tanker left Fujairah on Friday after the repairs were completed.
The Strait of Hormuz, which separates Oman from Iran and is the gateway to the oil-rich Gulf, is particularly vulnerable because of its maximum width of around 50 kilometres (31 miles).
The Bahrain-based US Navy Fifth Fleet said the strategically important waterway, through which an estimated 40 percent of global oil exports passes, remained open on the day of the reported explosion.