[AdmSmith]

BAGHDAD, Iraq (CNN) -- Twenty-five heavily armed foreigners holed up inside the Imam Ali Mosque in Najaf have rigged it with explosives and are threatening to blow up the building if attacked

http://www.freerepublic.com/focus/f-news/1192149/posts

Expect the Mosque to blow up. This is the purpose of the operation by these "foreigners". Objectives:

1) engage the Shi'ia into a full conflict
2) make sure that Najaf (in Iraq) will not take over the role of Qom (in Iran) as the center of Shi'ia interpretation.

This points to the Revolutionary Guards as the source.
However, the destruction would as well fit into the plan of the Salafists/Wahhabis to destroy all "polytheistic" shrines.

I think that the Revolutionary Guards accept the loss of the Mosque if they obtain 1) and 2) above.
Blame it on al Qaeda and the West

[nuconvert]

Hmmm.........I don't really understand what this would accomplish now that word has gotten out that the mosque is rigged with explosives. (if that's the case).
Seems to me, people would be really angry at al Sadr and his guys for doing that. Had they kept it a secret, that would be different.

[freedom44]

It's the Revolutionary Guards or the Basiji [volunteer hard-liners who regularly come to the calling of Iran's leader].