SAN DIEGO -- An activist once tied to the radical Earth Liberation Front was sentenced Thursday to a year and a day in federal prison for showing people how to make a fire bomb.

Rodney Coronado, 41, pleaded guilty on Dec. 14 to a rarely used federal law that makes it a crime to teach how to make a destructive device that could be used to commit arson. A jury deadlocked in his trial three months earlier.

The defendant could have faced up to 20 years behind bars if convicted.

Coronado told U.S. District Judge Jeffrey Miller that he wanted to move on with his life, which includes a new wife and two young children.

"I have done things in my past that I now regret," Coronado told the judge.

The defendant, who lives in Tucson, Ariz., said he has separated himself from radical groups such as the ELF and Animal Liberation Front.

"My life is about moving on from associations in general," Coronado told the judge. "I don't think future federal trials are conducive to a healthy marriage. My responsibility is to my family."

Coronado said his sentence was fair and asked to allowed "to start my life again."

Miller applauded the defendant for accepting responsibility for his actions and for his "rather dramatic" life change, "in a sense taking a new path in life."

The judge said Coronado's prominence in the activist community was "undeniable."

Miller said the defendant's current views on non-violent solutions to environmental and animal rights concerns could help moderate radical instincts that others have.

Coronado -- who is free on bail -- was ordered to report for custody no later than May 12.

Once he is released from prison, Coronado will be prohibited from associating with the ELF, ALF, or any other activist groups that promote violence to further their cause, Miller said.

Coronado was arrested on Feb. 22, 2006, and charged with teaching and demonstrating the making of a destructive device before dozens of people in Hillcrest on Aug. 1, 2003.

The defendant first described his past criminal conduct to the crowd, including sinking whaling ships and burning research facilities to the ground, prosecutors said.

Coronado then spoke approvingly of arson as the most effective way to advance his radical environmental agenda, according to prosecutors.

Just 15 hours after a $50 million arson fire destroyed an apartment complex under construction in the University Towne Center area of San Diego, Coronado described and demonstrated how to make a crude incendiary device using a plastic container filled with fuel mixture, a sponge and an incense stick.

A banner with the name Earth Liberation Front on it was found near the blaze.

In 2004, Coronado was charged for his role in interfering with a hunt for mountain lions in Sabino Canyon Recreation Area near Tucson. In 2006, he was sentenced to eight months in federal prison for that action.