New York - Senior U.S. intelligence officials tell ABC News new intelligence suggests a small al Qaeda cell is on its way to the United States, or may already be here.
The White House has convened an urgent multi-agency meeting for Thursday afternoon to deal with the new threat.
Top intelligence and law enforcement officials have been told to assemble in the Situation Room to report on:
--what steps can be taken to minimize or counter the threat,
--and what steps are being taken to harden security for government buildings and personnel.
"It suggests they have information that the cell or cells coming this direction want to attack a government facility," Brad Garrett, a former FBI agent and ABC News consultant, said.
Law enforcement officials say the recent failed attacks in London have provided important new clues about possible tactics.