Just reported on CNN that one bomb was a pressure cooker bomb. This was M.O. for previous case.

[Lint Head]

Foiled Fort Hood Terrorist Was Making a Bomb from a Pressure Cooker

Naser Jason Abdo, a US Army Private 1st Class who had gone AWOL earlier this month from Fort Campbell in Kentucky, was arrested this week in a motel room near the Fort Hood army base in Killeen, Texas. The tip-off came from a gun store clerk who had called in a "suspicious purchase," the NY

http://gawker.com/5825782/foiled-fort-hood-terrorist-was-making-a-bomb-from-a-pressure-cooker

There are several other reports of pressure cooker bombs used around the world.

[jberryhill]

1. Common IED

http://nfttu.blogspot.com/2006/03/pressure-cooker-bombs.html

The Department of Homeland Security issued a warning a while back about such devices. They issued a guideline in February 2004 about them. According to DHS,

Typically, these bombs are made by placing TNT or other explosives in a pressure
cooker and attaching a blasting cap at the top of the pressure cooker. The size
of the blast depends on the size of the pressure cooker and the amount of
explosive placed inside. Pressure cooker bombs are made with readily available
materials and can be as simple or as complex as the
builder decides. These types of devices can be initiated using simple electronic components including, but not limited to, digital watches, garage door openers, cell phones or pagers.

[drm604]

2. Interesting.

The Taliban also uses pressure cookers sometimes.

http://www.thenews.com.pk/Todays-News-4-171394-Arrested-Taliban-city-chief-killed-by-

So, while my gut feeling is domestic terrorism, the fact that pressure cookers were used doesn't prove much.

[cali]

3. evidently common in Pakistan

http://www.thenewstribe.com/2013/04/08/pressure-cooker-bomb-recovered-from-rickshaw-in-karachi/

http://www.dailytimes.com.pk/default.asp?page=2013\04\15\story_15-4-2013_pg7_10

http://www.thenews.com.pk/Todays-News-4-171394-Arrested-Taliban-city-chief-killed-by-

[Ian David]

4. We should look very closely at Paula Deen. n/t

[Lint Head]

5. Ha!

[pinboy3niner]

6. LOL!

Butter residue at the scene will be the smoking gun.

[octoberlib]

7. Lol

[R. Daneel Olivaw]

8. It sounds like something right out of the anarchist's cookbook.

Homegrown.

[cali]

9. actually its use is common in Pakistan and Afghanistan

pressure cookers are used a lot (for food prep) in both those countries. There have been several pressure bomb attacks around Karachi just in the last week.

And they can be incredibly lethal. The 2006 Mumbai train bombing which killed over 200 and injured over 700 was done with pressure cooker bombs.

Doesn't mean that the Boston attack isn't homegrown but it's nothing that would indicate that it is.

[ProgressiveProfessor]

15. I did not find that in there

Just thumbed through it to check.

You see them in Afghanistan and Pakistan

[applegrove]

10. That is the Taliban or al qaeda in Afghanistan MO.

[davepc]

11. Pakistani ISI as 'retaliation' for the Bin Laden raid?

Since we're just spit balling.

[ProgressiveProfessor]

16. ISI would have gone with higher yield explosives

[Bucky]

19. In that case, I'm going with unrepentent Czarists avenging the 1918 occupation of Arkangelsk

Those Russian Whites can be such diehard fanatics...

[Llewlladdwr]

21. I still think this is disgruntled Anarchists.

This attack was retaliation for the execution of the Anarchists Sacco and Vanzetti by the state of Massachusetts. The robbery/murder that lead to their trial and execution occurred on 15 April, 1920.

[Bucky]

22. What do anarchists have to be disgruntled about? We have no government, the world's in chaos...

If I were an anarchist, I'd be positively gruntled about the state of the nation these days...

[Fla_Democrat]

23. White Russians have kicked my butt..

on more than one occasion.

[Logical]

12. Why a pressure cooker vs. any other sealed container? n-t

[davepc]

13. Because they're purpose built to withstand the pressure

Any other regular sealed container would rupture too early.

[Retrograde]

14. Physics: Pressure cookers are designed to withstand more force than

common pots: the build-up of pressure in the sealed vessel raises the temperature of the contents well above the normal boiling point of water and lets the contents cook faster. If the cooker is damaged, or the seal fails (like if something explodes inside) all that extra energy is released all at once.

I use a pressure canner (like a pressure cooker, but much bigger) regularly for canning, and it requires continual monitoring to make sure it's properly vented before the weight that causes the pressure to mount is attached, and that the pressure stays in the safe range throughout the canning process. If one were to put an explosive device inside one and seal it without the proper steps, I'd suspect the rapid increase in pressure would rupture any seal and send the contents flying: my mother once put a hole in the ceiling with a defective pressure cooker, and she was trying to keep things under control.

[Logical]

17. Thanks! n-t

[pnwmom]

20. Yeah, but this really doesn't make much sense for a bomb.

Somebody or other on TV today was saying that the damage was probably less than it would have been because the pressure cooker helped contain some of the force.

[golfguru]

18. Pressure cookers are cheaper than say an oxygen tanks

and are available at many stores and on-line. Photo ID cards may be required for pressure cooker purchases.