Pressure Cookers- Why Pressure Cookers?
OK they have identified pressure cookers as the container for the low-explosives. Why pressure cookers? Because they are a fat pipe-bomb. And low explosives require a build-up in pressure in order to blow up stuff. So you have this ready-made pressurized container. And it comes with holes in the top so you can run wires from the outside to the inside. Then you just seal around the wires and you have your nice big pressurized chamber.
So a pressure cooker could hold 10-20 pounds of low explosive. Yes pressure cookers could also hold high explosives but unless your high explosive is TATP you don't need a container.
Something else that bothers me is there are explosive-proof trash cans. Every city needs to ante up and purchase those, especially places where they have large events. With those trash cans all the force is directed up through the trash can opening.
Another issue is that the "experts" on TV are talking about tool-marks. Thanks butt-heads. Now the perps know to ditch their tools.
Still no word on the type of explosive. I take that to mean they just aren't releasing that information because we have the technology to make that determination and I am sure the FBI has access to it.