He's known as the "human firewall."

Massapequa native Shawn Henry is the head of investigating computer crimes for the FBI, and after he was introduced with that informal title, he talked Tuesday of the breadth of the computer-crime problem facing the country and the world at a conference in New York of many of the world's computer experts.

Computer crime is "the most critical threat to our way of life other than weapons of mass destruction," Henry, 46, a graduate of Hofstra University, said at the International Conference on Cyber Security, sponsored by the FBI and Fordham University.

"Terrorist groups and organizations are trying to inflict the same type of damage [through hacking] as they did in 2001 by flying planes into our buildings," Henry told several hundred computer professionals in law enforcement, government, industry and academia at the start of the three-day conference at Fordham Law School.

But terrorists are not the only ones who realize that the nation's and the world's economy, along with its military and industrial secrets, reside on the Internet.

International criminal gangs have mushroomed in recent years, and hackers are no longer just computer-savvy teens looking to make a name for themselves.

Sophisticated, organized bands of thieves are already stealing "hundreds of millions of dollars a year" through a wide variety of computer scams, Henry said.

Henry said his father was a New York City police detective, and he once relayed notorious bank robber Willie Sutton's answer about why people rob banks: "Because that's where the money is."

"Now the money is on the network," Henry said.

To combat computer crime, the FBI uses informants and agents to infiltrate computer-crime rings and also makes alliances with police agencies around the world to work against both terrorist and ordinary criminal hackers, said Henry and his chief deputy, Christopher Painter.

Before he joined the FBI's computer division, Painter was a federal prosecutor in Los Angeles who jailed one of the first of the widely publicized hackers, Kevin Mitnick.

In theory, the infiltration technique is the "same as infiltrating organized crime in this city," Henry said, referring to the past arrests of the leaders of the five traditional organized-crime families in New York.

Henry conceded that the fight against computer crime is constantly evolving because of the cleverness and sophistication of the hackers.

"The offense outgrows the defense," he said.