President Barack Obama has ordered a "surge" of federal air marshals to be in place by Feb.1 in what officials said was a "race against time," with other suicide bombers believed to be in the terrorist pipeline, although there is no specific imminent threat, federal officials told ABC News.
Under a preliminary plan, the officials said the already existing federal air marshal force of more than 3,200 personnel would be deployed almost exclusively to overseas flights flown by U.S. carriers.
Domestic high-risk flights will be covered by agents from other federal law enforcement agencies who were trained as air marshals in the wake of the Sept. 11, 2001 attacks.
"The personnel we trained back then comprised a kind of reserve air marshal force and they are now going to be borrowed on orders from the President to work domestic flights," said a senior law enforcement agent briefed on the plan.
At the time of the Sept. 11 attacks, there were only 32 federal air marshals.
During his Tuesday speech on air security, President Obama said he had ordered "concrete steps" to enhance security, including "more air marshals on flights."
Officials said the augmented force of air marshals would include agents from other departments within the Department of Homeland Security, including Customs, Border Patrol, ICE and the Secret Service.
The officials said intelligence reports and the debriefing of the accused underwear bomber, Umar Farouk Abdulmutallab, indicated that there could be more than a dozen other young men trained for suicide missions against U.S. aircraft.
"The rush is to get our people in place before they get theirs launched," said the senior law enforcement official.
"We are going to try to cover every single U.S. flag carrier flight from overseas into the United States," the official said.
Administrative officials from the Federal Air Marshal program were ordered to leave their offices and take flight assignments, the official added.
"Most of us have not had a day off since the attempted bombing on Christmas," the official said.