Unabomber corresponded with CBS News Colorado's Rick Sallinger while at Supermax in Colorado in 1999

Last Saturday, the man known as the Unabomber died from an apparent suicide in prison in North Carolina. Ted Kaczynski was 81 years old.

He spent much of his life sentence behind bars at the Supermax prison in Colorado. He admitted to committing 16 bombings between 1978 and 1995. 

Three people were killed, while 23 more were injured in his targeted attacks.

CBS News Colorado reporter Rick Sallinger wrote to Kaczynski in 1999 in hopes of gaining an interview if not in person, by phone or mail. The response led to more than a dozen letters from one of the most notorious criminals in modern American history.

With Kaczynski's death, Sallinger looked back at some of the correspondence.

"Dear Mr. Sallinger, I have no respect for most journalists," he wrote. 

That is how the first of 13 letters from Ted Kaczynski began. 

He wanted to insist that a former neighbor named, Chris Waits, was making false claims about him.

So, CBS News Colorado went to Lincoln Montana, where the man known as the Unabomber had lived in his infamous shack.

Waits wrote a book about his neighbor called, "The Secret life of Ted Kaczynski." It detailed previously unknown environmental related attacks attributed to Kaczynski. 

Waits says there was a booby-trap that could have decapitated motorcycle riders.

"He took the wire and wrapped it around the tree both sides and pulled it tight," he said. 

Waits laid out more of what he says was a series of local crimes aimed at common elements of today's industrial society.

Kaczynski, who disdained the modern world, hated snowmobiles.

"During the winters, when I got tired of the snowmobiles and other disagreeable intrusions in the area of my regular cabin, I would hike out to my hidden shack," he wrote to Sallinger. 

In one of his letters Kaczynski admitted to what he called, "monkeywrenching" activities.

"I put sugar in the gas tanks and slashed the tires," he wrote. 

And heavy equipment was often the target of mysterious vandalism.

"I wish I had destroyed as much machinery as Waits claims. I'd be proud," he noted. 

It was signed yours very truly Ted Kaczynski.