Someone posted a link to a page of "broken arrow" incidents yesterday, and I recalled reading this one a while back.

To me it's the scariest broken arrow case. Two bombs were dropped from a disintegrating B52. One of the bombs parachuted into a tree with 3 of the 4 arming switches live. The other disintegrated in a field with live arming switches. The plutonium 'pit' was recovered, but most of it is still buried in that field.

It's a bloody miracle that neither went off.