Discovery Gunman James Lee's Sordid Past as a Human Smuggler

Sept. 2, 2010— -- James Lee, the bomb-laden gunman who was killed by police in the lobby of the Discovery Channel, was once convicted and imprisoned for smuggling illegal immigrants into the country from Mexico.

The revelation that Lee had once smuggled illegals contrasts sharply with a hate-filled manifesto he left behind in which he describes illegal immigrants as "disgusting filth" and their children as "anchor baby filth."

As his smuggling history came to light, new details emerged about Lee's deadly confrontation with police on Wednesday.

"I'm ready to die," Lee told police negotiators, Montgomery County Police Chief Thomas Manger told ABC News.

"My sense from listening to him was that he had no intention of leaving alive," Manger said.

Police also said today that the gun he used to menace his hostages and police was a starter's pistol. In addition, authorities discovered and safely detonated more four explosive devices found inside Lee's home.

Documents in the 2003 people smuggling case highlight Lee's descent into isolation and despair.

According to a copy of his plea agreement and a jailhouse confession written to the judge on the eve of his sentencing, Lee was choked and robbed in a Tijuana, Mexico, hotel room, before his assailants induced him to become a human trafficker.

"There I was in a Tijuana hotel being further subjected to more of life's brutality. There I was just being finished being choked and robbed. Then they offered me work. I had nothing left so I tried it. I started to smuggle people for them," Lee wrote Judge Barry Ted Moskowitz in August 2003.

He quickly came to like the job.

"For one brief moment in my whole worthless life I felt good about myself. I felt like I was really helping people. I have never saved a person's life, but it felt the same as I imagine it would have felt… For once my life seemed to actually benefit the lives of others," he wrote to the judge.

Lee was arrested trying to smuggle a woman in a concealed compartment of his car through the San Ysidro border crossing in southern California and was sentenced to 18 months in prison, according to court documents. He later said he was ashamed of his people smuggling.

The jailhouse letter also offers eerie foresight into Lee, who described his life as "a living, breathing nightmare."

"When I get out of prison, I undoubtedly will have the same personality traits as I had before. I wish I could point a finger at someone or something and magically be someone else.... I don't know if my life will end with a happy ending, but all I ask is for an ending that is not in prison," he wrote.