The WASP knife is more lethal than any other. Created for hunting dangerous animals, it kills on impact by injecting a frozen ball of compressed gas into the body of the prey, exploding the organs of the animal. Available to buy online, the British police is worried about the implications the weapon could have if it falls into the wrong hands.

As you can see in the video, which was published by its manufacturers, the WASP knife injects a frozen ball of compressed gas into the body, which, once released, swells to the size of a basketball. The UK's West Midlands Metropolitan Police has already received instructions to prevent the circulation of the knife. A difficult task, seeing as it can be bought online. If anything, the announcement of these measures has probably fuelled the weapon's popularity even more.