Sorry to say, I have no sympathy for scumbags. No matter where they may be, or what nation they call home. Anyone guilty of multiple murders SHOULD be made an example of. It wasn't too long ago in US history where executions were done publically.
The last one being done in 1936.
(edit: though i fear race may have been a factor, so maybe thats not such a great example)
Nonetheless, in the case of someone proven guilty of multiple homicides, I think capital punishment should be given, and carried out more often, as I do not believe it is possible to rehabilitate such people. They are a waste of good oxygen.