No time for hazmat?
It seems that LA police completely missed something shady happening that was not only reported by the public but recorded by a securicam: J. Random Stranger poured a bottle of mercury out on a subway platform, and the hazmat crew arrived eight hours later to clean up the spill. The Joint Terrorism Task Force says that this wasn't even a criminal act, which it probably wasn't but for future reference it actually is because mercury is toxic, and in fact there are special procedures that must be followed to clean it up. However, the guy who spilled the mercury hunted for a way to call for help after he did so, which leads me to believe that it was, in fact, an accident. Generally, if you're up to something shady like that you'd plan it better, and place the call from somewhere else.