Man Behind Iraq's Reign Of Terror

CIA voice analysis of a video posted on an Islamic Web site earlier this week shows that the hooded man in black who killed American hostage Eugene Armstrong is Abu Musab al Zarqawi.

Armstrong's body was found in Baghdad. A U.S. military officer tells CBS News Correspondent Sheila MacVicar the U.S. believes Armstrong had only been dead for a short time and therefore Zarqawi had not been far away.

Back in Afghanistan in 1991, when he was a militant with a reputation for thuggery, Salah al Hami became Zarqawi's brother-in-law.

Al Hami listened to the tape of the death sentence pronounced on American Nick Berg.

"It's possible they tampered with the recording," he says. "I don't want to make a mistake, but I believe it is his voice."

If the CIA and al Hami are right, it would make Zarqawi a rarity in the world of terrorist leaders: the blood of his victims on his own hands, rather than leaving his foot soldiers to do his bidding.

"Today Zarqawi enjoys a status which is as much as Osama bin Laden inside Iraq," says CBS News terrorism consultant Rohan Gunaratna. "He is regarded as the most celebrated Mujahedeen in Iraq today."

Zarqawi isn't his name, but the name of the town in Jordan where he grew up; where his family, including his son, still lives.

He spent his youth drinking and brawling, until he found religion, and then, jihad.

More than a decade ago, he fought in Afghanistan, then he was jailed in Jordan for plotting attacks on Jewish targets.

It was in prison, according to former inmate Yusef al Rababa, that Zarqawi became both more extreme and a leader.

He was tortured frequently, he says, and that made him a fanatic.

After prison, Zarqawi went back to Afghanistan's training camps.

Intelligence agencies say Zarqawi was in contact with bin Laden and that bin Laden may have given him money. But even the experts can't agree if Zarqawi was ever a full member of al Qaeda. We do know that he quickly set up his own training camp and that he competed with bin Laden for recruits.

"Bin Laden gave him in the past, maybe a kind of fighting spirit, and kind of inspiration," says Rolf Tophoven of the Institute for Terrorism Research and Security. "But today, he is working by himself."

When the Americans bombed Afghanistan, Zarqawi was still an obscure terrorist leader looking for a new fight. He found one in Iraq.

He's claimed responsibility for much of the violence in Iraq: the car bomb that drove the U.N. out of Iraq, the suicide bombings of police stations and political offices. With his bombs targeting Shi'ite Muslims, he's accused of trying to incite a civil war.

"The point of crystallization, the point of culmination is the Iraq war," says Tophoven. "Today, we see that the militant Islamists go to Iraq to fight the infidels, the Americans, the allied forces.

"Zarqawi is one of the main benefitters."

He has the money, the recruits willing to kill themselves, and again, he has the attention of the world waiting to hear the fate of his third hostage.