Boy sprayed by cyanide explosive: ‘By the grace of God I’m still alive’


POCATELLO — The family of a teenage boy sprayed by a cyanide explosive that killed their dog is outraged they weren’t told the device was planted near their home.

Canyon Mansfield, 14, went on a walk Thursday afternoon with his family’s 3-year-old yellow Labrador, Casey, on a hill behind their Pocatello home on Buckskin Road.

“I see this little pipe that looked like a sprinkler sticking out of the ground,” Canyon told “I go over and touch it. Then it makes a pop sound and it spews orange gas everywhere.”

The orange gas was cyanide, and it sprayed into Canyon’s left eye and on his clothing.

The teen grabbed some snow and washed his eye out but then realized Casey was having problems.

Canyon was walking with his dog, Casey, when they discovered the M-44 explosive. | Courtesy Theresa Mansfield

“I look over and see him having a seizure,” Canyon said, holding back tears. “I ran over and he had these glassy eyes. He couldn’t see me, and he had this red stuff coming out of his mouth.”

Canyon ran down the hill and inside the house to his mother.

“He said, ‘Mom, Mom, there’s something wrong with Casey,'” Theresa Mansfield recalled. “We ran back outside and up the hill and by the time we got there, Casey had died.”

Theresa called the police and then contacted her husband, Mark, who is a medical doctor.

“I hurried home, and the first thing I did was try to resuscitate the dog,” Mark Mansfield said. “Unfortunately I exposed myself to cyanide and had no idea.”

This M-44 cyanide explosive discharged behind the Mansfield’s home Thursday. | Theresa Mansfield.

It took hours after emergency crews arrived and help from multiple agencies to learn Casey had died from exposure to an M-44.

M-44s are spring-activated devices that release cyanide when they are activated through upward pressure or pulling. The US Department of Agriculture uses the devices to control coyotes and other predators.

“We didn’t know anything about it. No neighborhood notifications and our local authorities didn’t know anything about them,” Mark said. “The sheriff deputies who went up there didn’t even know what a cyanide bomb was.”

The Mansfields have lived in their home nearly 10 years and have never seen M-44s in their neighborhood. They say the one triggered Thursday was planted on the borderline of their property.

“We weren’t aware, and nobody told us,” Theresa said. “There was nothing posted up on the hill saying to beware or be careful.”

Canyon was rushed to Portneuf Medical Center for treatment and his family said they and Bannock County sheriff deputies who responded to their home had blood drawn to make sure they were OK.

On Friday, US Department of Agriculture Wildlife Services told this is the first unintentional discharge of an M-44 in Idaho since 2014.

“Wildlife Services understands the close bonds between people and their pets and sincerely regrets such losses,” R. Andre Bell, a spokesman for the US Department of Agriculture, said in a statement. “Wildlife Services has removed M-44s in that immediate area … and is completing a thorough review of the circumstances of this incident … to determine whether improvements can be made to reduce the likelihood of similar occurrences happening in the future.”

“If you plant bombs by our house, just tell us.”

A bag containing the clothes Canyon wore Thursday now sits outside the Mansfields home. | Nate Eaton,

The clothes Canyon was wearing when the explosive went off now sit in a sealed plastic bag since the Mansfields are unsure what to do with them.

“We couldn’t even have a proper burial for Casey because we didn’t know how to deal with cyanide,” Theresa said. “No one knows how to deal with cyanide.”

Canyon Mansfield hugs his father, Mark, in their backyard. | Nate Eaton,

The Mansfields said, as of Friday, nobody from the US Department of Agriculture has contacted them to apologize for what happened. They wonder if other explosives may be hidden in the hills surrounding their home.

“If you plant bombs by our house, just tell us,” Canyon said. “By the grace of God I’m still alive.”

His parents say they hope no other family has to endure what they’ve been through.

“300 yards from this swingset next to my house there were 2 cyanide bombs. It kills anything. It almost killed my child and it did kill my dog,” Mark said. “I don’t want it to kill my neighbors.”

Theresa added, “Canyon is lucky to be alive. Thank God. Thank God that he is OK.”



  • Winston says:

    The military has been banned from using chemical weapons but government agencies can plant them near residential areas? Who’s bright idea was this?

  • PNC13 says:

    Wow… Just… wow. More federal idiots. Get out! Trump is right. Reduce this federal government now. Too many idiots.

  • Pamsie says:

    Never been so stunned by a story, where is the outrage?

  • Dave Harker says:

    Seriously! …. that is insane that these are just sitting around for anyone or anything to be killed by them … what the heck are they thinking ! I am finding out more about this for sure and doing whatever it takes to see that they are never used again ! L

  • KelleyBeld says:

    Trump will protect the livestock and ranching industry, but not people. Expect more of the same – everything is expendable including children, pets, or anything else if it gets in the way of more profit for the oligarchs.

    • Eleanor Cummings says:

      Stop right there, numb brain‼ Are you a seer or clairvoyant that you know what President Trump will do?? This is one of the reasons I ditched the democrat party after being raised in a democrat family! I was a democrat from the early 50’s to the mid 90’s.Your democrat part today is NOT what it was when I was young. Now you people want to think the worse of the man without giving him a chance. You totally gross me out, you’re so disgusting.

  • Kir says:

    Thank you so much for your informative and thoughtful post. I wish everyone could read it.

  • David Rice says:

    But coyotes do not harm livestock. I’ve been a cattle ranch worker for 16 years.

    • James Nielson says:

      Seriously. We might as well be poisoning eagles. Anything to protect our… cats, chickens and rodents. You know, all of that precious livestock that coyotes rob us of. And let’s not forget unattended dog food!

  • CC1980 says:

    Sue the living daylights out of the POS that planted these landmines, along with having them charged with attempted murder of a child and murder of an innocent dog.

  • Sharon321 says:

    Unfortunate incident but, many times domestic dogs are responsible for livestock attacks and if this occurred on private property it would not occurred without trespassing. Maybe parental supervision is partly to blame. Too many seem to think it is OK to poison rodents with the same poison they don’t want livestock owners allowed to use. So it is unfair to say ranching is subsidized. Losing over a hundred sheep to coyotes is quite an expensive subsidy to coyotes. Especially as coyotes mostly just kill for some cruel amusement.

    • James Nielson says:

      I know the paperwork’s probably not fun, but ranchers get reimbursed for livestock lost to wild predators. Livestock fed on public lands. I sympathize with them (I’m related to them), but to pretend it isn’t subsidized is to just pretend the word means whatever we want it to. And isn’t there just too much of that these days? If we have the guts to say “yes it’s a subsidy” then maybe we can get to doing a cost-benefit analysis of that subsidy. Personally, I think ranchers need to cowboy up, take care of their own livestock like grandpa did, and pass the cost of doing business on to customers that (I hope) place some value on living in a country that still HAS wildlife.

  • rumcrook™ says:

    This is an example of a government that is too large and how it makes the citizens smaller. Ponder this, it is ilegal for you to set a lethal trap for an intruder breaking into your home through a door or window that indiscriminately harms or kills. That is a fact. It is decided case law. If you rig a device and someone breaks in through a window and they are killed you will go to jail.——————now, take a look at what the governemnt did here sans consequences, no one is fired not even a bother to the feds who did this. They set a deadly indiscriminate trap that almost got a curious young boy killed literally just outside his home, it did kill the family dog and endangered several responding adults. Yet no one was arrested???? If my child had been harmed by something like this there wouldnt be a hole deep enough for the perp to hide in.

    • Eve Moran says:

      Please review Baddogged’s comment above. This shouldn’t happen to any family, but it does and we should demand accountability at all levels for government services.

  • Eve Moran says:

    Thank you baddogged!
    I am cutting and pasting your comment wherever I can. We need to look at the whole picture instead of only single incidents. I remember reading about these traps as a child, in the book “A Dog Called Kitty” and you’re absolutely right: they are deployed on behalf of ranchers, at the expense of nearby communities. There has to be balance.

  • Pablo Jay says:

    Prosecute the people responsible.

  • MothersEarth says:

    People need to make extra effort to be aware of what is in their area. More animals and people are killed by predators and could ever be killed by predator control. If your children and animals are going to Adventure off of your property, you need to know what is around where they are going.

    • Forever39 says:

      What people are you referring to? People killed by coyote? Wolves, bears? I think not. You are condoning this horror, and your handle is MothersEarth? You are a First Class……hypocrite! (I’d like to insert another word).

  • Elton woods says:

    Wildlife services “regrets” loss of pets!? What about the humans that almost died? Think their smart enough to take that up in their “review” meetings and apologizes?
    Government at its worst!

  • Forever39 says:

    Why is it ok to do THIS to a coyote? Are they undeserving of life? Though more intelligent and beautiful than ANY dog. I don’t get it.

  • Forever39 says:

    Once again, why is it ok to do THIS to WILD animals, that are far superior in genetics, intelligence and beauty to their domestic counterparts…but only those ‘non-targeted’ (domestic) species cause any discomfort to people like yourself??

    • Brian R Gard says:

      You are over reacting and judging something you don’t know a damn thing about! Actually I deplore the use of them on any account, they also kill antelope, moose, elk, bears, cougars, eagles, hawks, ect, ect – and for the record I DO NOT LIKE THIS EITHER, but my point is to encourage people to get involved to pressure the government to discontinue the practice. Your method is to attack the people on your side of the issue – which is destructive – so take a long hike and chill! (Quit your incessant ‘whineboobing’….

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