Jim Mone, Associated Press
A recently fired nuclear power plant employee upset with his union was arrested last week with leg irons, igniter fluid, propane, explosives and 500 rounds of rifle shells in his car, according to charges.

MINNEAPOLIS — A recently fired nuclear power plant employee upset with his union was arrested last week with leg irons, igniter fluid, propane, explosives and 500 rounds of rifle shells in his car, according to charges.

Robert J. Johnson, 58, of Sioux Falls, S.D., was charged May 21 in Ramsey County District Court with four counts of terroristic threats. He was arrested on May 20, and told police that he had planned a “surprise attack” that evening for the North Central States Regional Council of Carpenters union hall in St. Paul.

“Johnson said he had ammunition and a bear trap in his car,” the charges said. “Johnson clapped his hands together and said, ‘Boom. Tick tock tick tock.’”

According to the complaint: Johnson met with the chapter president at the union office on May 12 to mediate problems at Johnson’s work site at the nuclear power plant in Monticello. Johnson began yelling and intimidating a union business representative, and was escorted out.

He was fired from the power plant the next day and later confronted the union business representative at the union office. Johnson allegedly called him names in order to prompt a fight. Johnson left, but returned the next day and harassed union staff.

Johnson had a history of being removed or fired from his jobs.

On May 16, Johnson appeared at the power plant and tried to fight other workers.

Two days later, he allegedly called the union hall and made threatening statements. He allegedly said that he would have a scope rifle on a hill if the union’s head didn’t resign, that he would be at the May 20 union meeting and that he was a Marine and “certifiably crazy,” the complaint said.

Johnson made a whistling sound like a bullet, and the union’s executive secretary-treasurer ended the call.

Johnson left three messages at the union office the day he was arrested. Police found him at the VFW in Monticello with a .40-caliber cartridge and two spent .410 shells.

His car, its license plate obscured by a bumper sticker, was towed and later searched. Johnson was questioned by St. Paul police.

“Johnson said he was pissed off and that he wanted to talk to Doctor Christ, his psychiatrist,” the complaint said.

Johnson told police he was upset with paying $3,500 a year for the union’s representation, that his real name was “Trouble” and that there would be trouble at the union’s meeting that night.

Johnson also denied that he planned to shoot anyone or threatened anyone.

“You have to save the union hall,” Johnson allegedly said toward the end of his interview with police. “Tick tock tick tock.”

Technicians and police canines searched union offices, grounds and vehicles nearby and found no explosives.

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