CHRIS MATTHEWS: How about the pressure cookers? Now, they're kitchen products. I was asking people, apparently any Wal-Mart, any, you know, Sonoma, whatever it's called. Almost any store, high end or low end or middle end, will have it available.
LARRY C. JOHNSON, FORMER CIA ANALYST: You can always tell what a particular brand it is and even trace it back to where that was produced. Itβs important to note that particular model, that type of explosive, has been very popular along the Pakistan/India border.
CHRIS MATTHEWS: what does it do to screw on top of aβ¦?
JOHNSON: It's not so much the scree -- they have developed a system for it: you put the explosives inside. Could have been ammonium nitrate, TATP. It was not likely a high military explosive because of the smoke color.
MATTHEWS: Why is the compression built up more?
JOHNSON: Itβs not so much the compression. It gives you something, you can hold it in there, can put some bearings in. It's a nice, convenient container. The detonator will go in through the top. You still have to figure out a way for that detonator to ignite.
MATTHEWS: What does it tell you these were set off sequentially, that one goes, then a couple seconds later another goes? How hard a project is that for an amateur, malevolent Unabomber type, and how much does it suggest an organized international operation?
JOHNSON: You know, take your scale of zero where you can't even open a door and ten being the world's best bomb maker, this is about a six. This means somebody did the prior planning. They knew how to develop the devices. They were able to set the timers in such a way they didn't detonate beforehand and detonated close enough to each other. This has been a hallmark of al Qaeda.
MATTHEWS: Closer to organized terrorism groups than a crackpot?
JOHNSON: Yes, absolutely.