When I was a kid, I heard about a revenge case—no idea if it’s true or not.

Simply put, it was that a plumber, because the law was unfair, had to take revenge himself. So he attached a piece of radioactive metal behind the rival family’s water pipe. Over ten years, the family members went on to die one after another from cancer, and in the end, not a single person survived. And the plumber finally surrendered to the authorities...
Was it because management wasn’t strict in that era, so it was still possible to obtain some radioactive materials...