SALEM, Ore. -- The father of a suspect in a bank bombing that killed two officers was arrested Tuesday.

Police said they arrested Bruce Turnidge, 57, on Potts Road near the town of Jefferson on charges of conspiracy to manufacture an explosive device and conspiracy to possess an explosive device in connection with the bombing. Bruce Turnidge is the father of Joshua Turnidge, 32, who already appeared in court to face charges in the case.

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Court documents show two law enforcement officers killed in the bank bombing last week believed the device was a hoax and were trying to open it when it exploded.

View Probable Cause Document Outlining The Case Against Joshua Turnidge

A probable cause statement in the case of bombing suspect Joshua Turnidge said Oregon State Police Senior Trooper William Hakim inspected and X-rayed a green metal box found Friday outside the West Coast Bank building in Woodburn.

The document said Hakim was confident it was a hoax device, so he took it inside.

The statement said a bank employee saw Hakim trying to open it while Woodburn Capt. Tom Tennant held it, and then it exploded.

Joshua Turnidge was arrested Sunday night at a home on Nolan Lane in northeast Salem on charges of aggravated murder, attempted aggravated murder, conspiracy to commit aggravated murder, assault, possession of a destructive device and manufacture of a destructive device.

He appeared in court for the first time Tuesday and answered "yes" twice to questions about whether he wanted a lawyer. He did not enter a plea.

In the brief hearing, he stood behind a transparent panel, wearing a green jail garment that exposed the tattoos covering much of his upper arms. He's due back in court Dec. 26.

After the hearing, prosecutor Matt Kemmy said again that authorities won't say what they think was the motive for the bombing.

Evidence Trail Leads To Turnidge

According to the probable cause statement, last Friday at 10:19 a.m. a man called in a bomb threat to the Wells Fargo Bank in Woodburn, which is close to the West Coast Bank branch. The man said "if 'they' didn't leave the building, all of them would die," the court document states.

The man said a cell phone would be found next to a garbage can, and that he would give further instructions on it. The man also said he would be calling the West Coast Bank.

Local police officers arrived at the Wells Fargo building, opened a garbage bin and spotted a cell phone on top of what appeared to be a package. Hakim and an FBI bomb technician were called. They examined the package and cell phone and determined it was a hoax device.

Woodburn police searched the area around the two banks for other devices, and a green metal box was spotted next to the West Coast Bank building.

Hakim, Tennant and Russell arrived at the West Coast Bank. After Hakim inspected and X-rayed the green box, he said he was "confident that it was a hoax device and that it could be taken apart to be placed into evidence."

Hakim brought the green box into the bank to work on it, with help from Tennant and Russell, and it detonated.

The court document clears up the mystery of why bomb technicians brought the bomb inside the bank -- because they thought it was harmless.

But it does not suggest a motive. Investigators and prosecutors have refused to talk about a possible motive.

However, it does reveal the trail that led to Joshua Turnidge.

Police said they think Joshua Turnidge purchased two Tracfones, including the phone found at the Wells Fargo bank, at a Bend Wal-Mart on Nov. 26. Airtime cards for the phones were purchased at a Salem Wal-Mart on Dec. 11, the day before the bombing. The two phones were activated on the morning of the bank bombing, the court document states.

Police obtained surveillance video showing "the subject who bought the two Tracfone airtime cards" walking out of the Wal-Mart to a blue early 1980s Chevrolet pickup truck. Investigators were able to determine the truck is registered to a Bruce A. Turnidge.

Police Sgt. John Troncoso wrote in the document that Bruce Turnidge is too old to be the person in the surveillance video, but he discovered Bruce Turnidge is the father of a Joshua Turnidge. Troncoso looked at Joshua Turnidge's DMV photograph and recognized him as the man in the surveillance video.

This past Sunday, Troncoso and another officer drove by Joshua Turnidge's residence and spotted the blue pickup, and he was arrested.

Joshua Turnidge's Neighbors 'Stunned' By Arrest

Marie Kenney, who lives nearby, said police asked her if they could conduct surveillance and watch Joshua Turnidge's house from her back window.

"A neighbor told us they arrested him and it was for the bombing," Kenney said. "And I was stunned. I mean, there's a bomber right next to my house. I couldn't believe it."

The Marion County District Attorney's Office said Joshua Turnidge was seen in surveillance photos that were released to the public Sunday evening. Hours later, authorities said, they arrested him.

"We know there is still a lot of hard work ahead of us, but this development will help bring relief to the local community and the officer's families," said Marion County Sheriff Russ Isham.

Earlier Sunday, Isham said cell phones and items that might have been used to make the Woodburn bomb were bought in the central Oregon city of Bend last month. Authorities would not elaborate on how cell phones might have been used. Bombers often use cell phone signals to remotely detonate explosives.

Deputy District Attorney Courtland Geyer said revealing anything about the "manner and build" of the bomb would hurt the investigation.

Woodburn Police Chief Scott Russell was critically injured -- he has lost his right leg from the knee down, and his left leg was mutilated, according to the court statement.

Marsha Elsom said she used to live next door to Joshua Turnidge, his wife and children. While she had heard about the bombing, she said she was shocked to learn her former neighbor is now accused of being behind it.

"I'm, like, really shocked because he was, like, a really nice guy. I'm sorry, I'm just shocked," Elsom said. "He doesn't seem like he would do anything like that."

Public records show the 32-year-old was arrested in Polk County in 2002 on charges of theft and forgery. But the charges were later dismissed.

Back in north Salem, neighbors didn't seem to know much about the man, either. A credible source close to Joshua Turnidge said he and his family had just moved into the rental house a week ago.

A tip line remains open at the number 1-888-780-5678. A reward for information is also still being offered.

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View: Surveillance Photos