Engineering - Mobile phone gun

This is what Airport Security found in a cell phone.
When you see the pictures below, you will understand why they want our cell phones to go through the x-ray machine.

Cell phone GUNS have arrived. Beneath the digital phone face is a .22 calibre handgun capable of firing four rounds in rapid succession - using the standard telephone keypad. European law enforcement officials are stunned by the discovery of these deadly decoys.
Only when you have one in your hand do you realize that they are heavier than a regular cell phone.