Nail-spiked cheese cubes have not been found in Chicago dog parks.
Dog owners went into a frenzy after a photo circulating Facebook depicted a handful of cheese squares laced with what appeared to be roofing nails. Notices attached to the photo claimed that such cheese cubes had been discovered at parks in Chicago and Massachusetts.
The Facebook thread falsely warned: "New trend at dog parks, nails in pieces of cheese, if you take your dogs to dog parks, be careful."
The threat was proven a hoax, though, and there are no confirmed reports of this happening at the alleged locations, according to Snopes.com.
The photo did come from an actual incident. According to Snopes.com, it was snapped in Buenos Aires, Argentina last July after a dog walker saw the cheese cubes on the floor of a kennel in the city's Centennial Park.