So serious did the American officials take the threat that the Federal Bureau of Investigation and the Department of Homeland Security has issued a warning to local police authorities across the country about an al Qaeda threat of targeting oil and natural gas assets including tankers.
The US officials came across the al Qaeda plot to blow up tankers while sifting through documents found in the Abbottabad compound where bin Laden was killed three weeks ago.
A joint intelligence alert issued by the FBI and Department of Homeland Security said that information had been received that al Qaeda had sought information on super oil tankers and was contemplating that spring and summer was the best time to approach these ships, apparently a hint to hijacking them and later blowing them up to create an "extreme economic crisis".
According to the advisory, al Qaeda wanted to target oil tankers in the Indian and Atlantic oceans, as well as the Arabian Sea, but the terrorist group "was opposed to targeting tankers in coastal areas with large Muslim populations".
In 2010, the intelligence bulletin said, al Qaeda tried to get information about the size, layout and construction of oil tankers to help with attack planning.
Al Qaeda also recognized the importance of pre-attack surveillance of a possible target and recommended conducting trial runs, it said.
The Homeland Security spokesman Matthew Chandler said in 2010 there was continuing interest by members of al Qaeda in targeting oil tankers and commercial oil infrastructure at sea.
But, it is unclear if any further planning has been conducted since the middle of last year, he said.
"We are not aware of indications of any specific or imminent terrorist attack plotting against the oil and natural gas sector overseas or in the United States," Chandler said in a statement.