Marvin John Heemeyer (October 28, 1951 – June 4, 2004) was an American automobile muffler repair shop owner who demolished numerous buildings with a modified bulldozer in Granby, Colorado, in June 2004. Heemeyer's machine was posthumously nicknamed the Killdozer.
Heemeyer held various grudges against town officials, neighbors of his muffler shop, the local press, and other Granby residents. Over about eighteen months, Heemeyer secretly armored a Komatsu D355A bulldozer with layers of steel and concrete.
On Friday, June 4, 2004, Heemeyer used the bulldozer to demolish the Granby town hall, the house of a former mayor, and several other buildings. He killed himself after the bulldozer became stuck in a hardware store he was destroying. No one else was injured or killed.On June 4, 2004, starting at around 2:15 p.m., Heemeyer began by driving his armored bulldozer through Mountain Park Concrete, owned by the Docheff family. At the time of the attack, Cody Docheff was at the concrete plant, screening topsoil at the gravel pit, when he got a notification over his radio that there was an explosion at the precast concrete shop.[1] Several employees attempted to stop the bulldozer by cramming objects into the treads in order to jam it, but to no effect. Cody Docheff, initially believing the dozer to be under remote control, fired a pistol at it and attempted to climb on top, to no effect, before engaging the bulldozer with his own front-end loader, again to no success. During this time, Heemeyer fired multiple rounds at the loader. A deputy from the sheriff's office arrived on the scene, followed by a Colorado State Patrol trooper, who was fired upon by Heemeyer. More deputies arrived and began firing on the dozer, attempting to destroy the cameras with gunfire, but were unable to penetrate the three-inch (7.6 cm) bulletproof plastic. At one point, Heemeyer charged at a firing position occupied by several state troopers, who evacuated mere seconds before he demolished it, with one eyewitness noting that had they taken any longer, they would have been killed.
After the concrete plant, Heemeyer turned onto Agate Avenue and headed south toward town at approximately 5 mph (8 km/h).[1] The officers at the plant requested a reverse 911 call be made to all residents in order to initiate evacuations. Undersheriff Glenn Trainer climbed atop the bulldozer and rode it "like a bronc buster, trying to figure out a way to get a bullet inside the dragon".[4] He also dropped a stun grenade down the bulldozer's exhaust pipe, with no apparent effect, and was later forced to jump down to avoid debris.
Heemeyer then advanced on Granby Town Hall, which had been hosting a story hour for children in its library when the rampage began. All occupants were evacuated only moments before Heemeyer reached the building, an hour after the rampage began. Heemeyer turned to the Liberty Savings Bank, where he aimed at the corner office where a woman who was a part of the zoning board worked.[1]
Police forces were unable to damage the bulldozer and so instead resorted to following it, jogging alongside it en masse. Heemeyer next targeted several street fixtures, such as trees and traffic lights, before moving on to the offices of the local newspaper, and in turn the homes of the Thompson family and their workplace. A scraper was brought up to try to stop the bulldozer, but it was pushed aside.[8]
Heemeyer next targeted a propane storage yard, firing 15 bullets at the tanks, some of which contained 30,000 U.S. gal (110,000 liters). Police were forced to hurriedly evacuate all residents within a thousand yards of the site, including a senior housing complex. Heemeyer then fired upon nearby power transformers, with a high risk of igniting the tanks, but struggled to find a good angle. Heemeyer hit the transformers once and missed his other shots. "Had these tanks ruptured and exploded, anyone within one-half mile [800 m] of the explosion could have been endangered", the sheriff's department said.[5] Twelve police officers and residents of a senior citizens complex were within such a range.[5] After leaving, he was engaged by another scraper, which he similarly defeated.[8]
At this point, local authorities and the Colorado State Patrol feared they were running out of options in terms of firepower, as the approximately 200[1] rounds fired by police had been ineffective up to that point, and that Heemeyer would soon turn against civilians in Granby. Governor Bill Owens allegedly considered authorizing the Colorado National Guard to use either an Apache attack helicopter equipped with a Hellfire missile or a two-man fire team equipped with a Javelin anti-tank missile to destroy the bulldozer. As late as 2011, Governor Owens's staff vehemently denied considering such a course of action. Members of the State Patrol, however, claim that to the contrary, the governor did consider authorizing an attack, but ultimately decided against it due to the potential collateral damage of a missile strike in the heart of Granby being significantly higher than what Heemeyer could have caused with his bulldozer.[16]
Heemeyer finally attacked the Gambles Store, targeting it due to the owner's involvement in the hearings about the batch plant.[8] As the bulldozer slowly plowed through the building, one of the previous scrapers was maneuvered onto the sidewalk behind Heemeyer's path, blocking him from retreating back onto the street, after which the civilian operator exited the vehicle and fled to safety.[17] Forced to continue forwards and unaware of a small basement on the property, Heemeyer dropped a tread into it, immobilizing himself. The radiator had also been damaged, and the engine was leaking, before failing. As such, it was noted that even if Heemeyer had been able to free himself, the bulldozer would not have been able to operate much longer.[8] About a minute later, at 4:30 p.m. MST,[1] one of the SWAT team members, who had swarmed around the machine, reported hearing a single gunshot from inside the cab. It was later determined that Heemeyer had shot himself in the head with a .357-caliber handgun.[15][18]
Police first used explosives in an attempt to remove the steel plates for fear of booby traps, but after the third explosion failed, they cut through them with an oxyacetylene cutting torch.[1] After getting inside, they found the access hatch and enough food and water to last a week.[1][8] Grand County Emergency Management Director Jim Holahan stated that authorities were able to access and remove Heemeyer's body at 2 a.m. the next day, on June 5.
