The information was sent in a note to federal and state law enforcement agencies, The Hill reported.
Matt Chandler said there was no evidence of any imminent threat or specific plans. He said intelligence gleaned from material found at Osama bin Laden's compound in Pakistan shows members were interested in "targeting oil tankers and commercial oil infrastructure at sea," he said.
The letter emphasized the importance of continued vigilance. Officials said nothing in the data analyzed so far shows al-Qaida had a specific target or had formulated plans for an attack.
"Our security posture, which always includes a number of measures both seen and unseen, will continue to respond appropriately to protect the American people from an evolving threat picture both in the coming days and beyond," Chandler said.