I would like to know if it is possible for an Imam in congregation to interrupt the prayer for some reasons. For example some of the praying believers have been attacked or a he's hearing murmur or something behind him or some part of then mosque (pillar/wall...) is collapsing.
It would be nice if you could quote an evidence.
One reason which seems clear is if the imam loses his purity, but i have never heard of an evidence for that and would know how this would be handled. While for the ma'mums there's a clear hadith.
And if this is possible acceptable i would like to know if there where other reasons beside the one mentioned above it would be acceptable and how it was/will be handled!