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, Weber County Jail
Thomas Zajac

SALT LAKE CITY — An Illinois man who planted a pipe bomb in the Salt Lake City Public Library nearly five years maintained his innocence as a federal judge ordered him to prison Thursday.

"I didn't have anything to do with placing that thing in the library," Thomas James Zajac told U.S. District Judge Clark Waddoups.

A jury convicted the 57-year-old heating and cooling company owner last fall of six charges related to the September 2006 bombing. The explosion damaged a third-floor window and forced 400 people to evacuate. No one was injured.

Waddoups sentenced Zajac to 35 years in prison followed by five years of supervised release. Under federal guidelines, the judge could have added at least seven more years, but said he settled on 35 largely due to Zajac's age.

"This is an inexplicable offense," Waddoups said, adding that it was "quite unusual" for a person of Zajac's intelligence and success in life to become so emotionally caught up in something that would lead him to violence.

At trial, federal prosecutors showed how Zajac became infuriated with Salt Lake police for arresting his son, Adam Zajac, for DUI in 2004. Instead of directing his anger at his son, Zajac traveled from Illinois expressly to place a bomb in the library as an act of revenge, they said.

The explosion was followed with unsigned letters claiming responsibility and threatening more bombings. One letter stated, "If one person isn't killed, I will go again."

Prosecutor Eric Benson said in arguing for a longer sentence that Zajac should never have the chance to go again.

Fortunately, he said, no one died in the explosion. "It could have killed one. It could have killed five," he said

But the blast did cause panic, chaos and fear. "It is the very definition of terrorism," Benson said.

Rather than talking with the police department about his beef, Zajac took matters into his own hands.

"Putting bombs in places is absolutely unconscionable," Benson said.

Zajac also faces federal charges in connection with a bombing in Illinois.

A federal grand jury there indicted him last year in the 2005 bombing of the Hinsdale, Ill., train station. Prosecutors say Zajac became enraged at police after his son was arrested on a traffic warrant. The pipe bomb was "virtually the same" as the one used in the Salt Lake library explosion, prosecutors said.

Zajac intends to appeal his Salt Lake conviction.