President Obama greets CIA employees at the Langley, Va., headquarters… (Reuters )
Reporting from Washington — Material seized when Osama bin Laden was killed show that Al Qaeda considered attacking tanker ships and other marine infrastructure last summer in an effort to force up the price of oil and damage the U.S. economy, according to U.S. officials.
The files don't suggest an attack at sea is imminent, or that terrorist planning progressed since last year, said Matt Chandler, spokesman for the Department of Homeland Security. But the FBI and Homeland Security officials issued an alert Friday to law enforcement and the energy industry.
Chandler said the alert urged "random screening, personnel briefings describing possible threats, procedures for reporting suspicious activities and the need for vigilance."
Another U.S. official said the intelligence added details to previously known information on Al Qaeda's interest in targeting the oil and natural gas industry.
The latest haul from Bin Laden's vast trove of documents and computer files emerged as President Obama traveled to CIA headquarters in Langley, Va., to thank the intelligence community for its role in the hunt for Bin Laden and the May 2 raid that killed him in Abbottabad, Pakistan.
Obama met privately with senior officials and about 60 spies and analysts who were most closely involved in the chase. He then spoke to about 1,000 employees who jammed the lobby. On the marble wall behind him were 102 stars that memorialize CIA officers killed in the line of duty.
Obama praised the analysts and case officers, most of whom who toil in anonymity, for "never giving up" on finding Bin Laden, and for keeping it secret as intelligence mounted that they may have located his compound.
"The work you did and the quality of information you provided made the critical difference," he said. The president said the clandestine operation would be studied "for generations to come."
The CIA was sharply criticized in Congress for providing inaccurate intelligence to President George W. Bush during the run-up to the invasion of Iraq in 2003, and some critics said the agency slanted its analysis to please the Bush White House.
Obama, in contrast, praised the CIA for collecting more intelligence and re-examining assumptions after it first began focusing on the Abbottabad compound last August.
"You didn't bite your tongue and try to spin the ball," he said. "You gave it to me straight, every time."
Obama drew chuckles when he said U.S. Navy SEALs not only killed Bin Laden, but "walked off with his files," and that "many of you are working around the clock" analyzing the material.
"Today every terrorist in the Al Qaeda network should be watching their back," Obama said. "We are going to pursue every lead."
It was Obama's third visit to CIA headquarters as president.
In another development, a missile fired by a drone aircraft controlled by the CIA killed four militants on the ground in North Waziristan region of Pakistan, according to news reports citing Pakistani intelligence officials. It was the seventh such attack since Bin Laden was killed.