He is Pakistani warlord Baitullah Mehsud, the accused mastermind of the Benazir Bhutto assassination. An emerging leader, sources say, who threatens to eclipse Osama bin Laden as the world's top terrorist.
Terrorism analyst Christine Fair says Baitullah Mehsud is running a training camp for suicide bombers in Pakistan's off-limits tribal region -- a magnet for radical Islamic recruits from Europe and potentially the United States.
"He may not be out there cultivating people to send them abroad, but people abroad may seek him out for the operations that they conduct back home or elsewhere," Fair says.
Officials suspect that's precisely what happened in the recent foiled suicide bombing plot targeting transit systems in Spain and four other European countries.
Operatives rounded up in Barcelona have been linked to terror training camps in the same Pakistan region where Mehsud is the supreme commander and where al Qaeda has found safe sanctuary.
Robert Grenier was a top official at the CIA.
"Given the fact that he is able to control territory that is extremely important to al Qaeda, that makes him a very important player," Grenier says.
Unlike al Qaeda leaders bin Laden and Ayman al-Zawahiri, who use very public propaganda to assert their power and build fear, Mehsud is a secretive tribal fighter who rarely shows his face outside his inner circle.
But Mehsud's message is just as threatening.
With his identity protected, Mehsud told the Arab network al Jazeera, "We want to eradicate Britain and America ...We pray that Allah will enable us to destroy the White House, New York, and London."
"He's saying the same thing that bin Laden said then years ago," Secretary of Homeland Security Michael Chertoff said. "And it doesn't mean that the attack's coming tomorrow, but yeah, it's certainly, he's the kind of person and his group is the kind of group that we need to mindful about."
While Mehsud's emergence from the shadows is worrisome, U.S. officials hope there's an upside. As one intelligence analyst put it, if he makes himself more visible, he'll be easier to eliminate.