Korsborn was a narcotics detective in the summer of 1973 when he got a warrant to search property in the 12300 block of Meridian Avenue south of Everett. He was looking for marijuana when he walked into the garage.
Inside he noticed stacks of what appeared to be gold bricks wrapped in plastic.
Korsborn consulted another officer, a military veteran who served in Vietnam.
"What's that?" he remembers asking.
"That's C-3," the officer said, referring to an explosive substance used in bombs detonated by fuse or electrical impulse.
Devices hooked to timers were found in drawers.
"I said, 'We're out of here,'" Korsborn said.
The officers had stumbled upon 106 pounds of C-3 plastic explosive. Three partly completed time bombs were found, along with 1,000 blasting caps, secret code books and electrical equipment.
Homes nearby were evacuated while an Army bomb squad from Fort Lewis was brought in to dispose of the ordnance.
Officials estimated the explosives could have leveled everything within a quarter mile of the house had they been rigged to blow.
Korsborn still has the police notes he took that day. His suspicions justifying the warrant proved correct. Police found a bag of marijuana seeds as well as a small amount of an unknown controlled substance.
The notes bring back memories of a scary day in Snohomish County's past.
The marijuana case turned into a federal explosives investigation.
Weeks later, fugitive Rodney V. Stephenson was captured near an Air Force radar station in California. He was armed when arrested on a federal warrant.
At trial, the defense told a federal jury that Stephenson had found the explosives in a remote part of Snohomish County and planned to use them for mining.
Federal prosecutors described the defendant as "a bomb factory operator."
Nearly four decades later, Korsborn watched with more than a passing interest as bomb technicians in Colorado disarmed devices in an apartment authorities say was rigged to kill first emergency responders. He's thankful no one was hurt in his hometown on that August day in 1973.
"It was pretty spooky," he said.
Eric Stevick: 425-339-3446; email@example.com.
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