The 45-year-old former military intelligence officer, whose name is protected by a publication ban, pleaded guilty to weapons charges in a Calgary court this week.
An agreed statement of fact, first reported by CBC, says he was arrested in January after his wife contacted police concerned that her husband might be suicidal.
When officers found him several hours later, they recovered firearms, body armour, possible bomb-making materials, schematics of the downtown skyscraper that houses Veterans Affairs and a plan to attack the seventh-floor offices. There were also photos and videos taken inside the building.
The man was arrested under the Mental Health Act and taken to hospital for treatment. He told officers he had planned to commit suicide.
Court documents say he had been in the military from 2008 until he went on long-term military disability in 2011. He was in a dispute with the department over the coverage of costs for his health issues, which included multiple sclerosis that he blamed on the H1N1 flu vaccine he was given while in the military.
When the accused was arrested at his parent's acreage west of Calgary he was dressed in camouflage pants and sleeping with a duffel bag near his head.
Inside the bag was a 40 calibre semi-automatic handgun that was loaded with a full magazine. They also recovered a .308 calibre rifle, a ballistic range finder scope for shooting long distances, a laser site for shooting at close range, night vision binoculars and 1,000 rounds of ammunition.
"Recovered off the accused's laptop was a written plan that contained notes made regarding the reconnaissance of the Bantrel Tower and a plan relating to what the Crown submits was a plan to attack the office of Veterans Affairs," the court documents say.
There were also jugs filled with chemicals, including bleach, muriatic acid and chlorine, empty suitcases with metal linings, 16 black sticks with a protruding fuse resembling dynamite sticks, carpenter nails, threaded pipes and six tubes of camouflage face paint.
Police also recovered black gun powder, 16 canisters of bear spray, 25 smoke grenades and a gas mask.
He has pleaded guilty to possession of a firearm weapon/device, possession of a prohibited/restricted weapon and possession of a weapon.
He has yet to enter pleas to four other charges including making explosives, two counts of careless use/storage of a firearm and unauthorized possession of a prohibited weapon.
He remains in custody and is scheduled to be back in court Nov. 27.
He will undergo a forensic psychiatric exam and isn't expected to be sentenced until sometime next year.
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