“Murder of Burglar”

How can people defending their own property be arrested for murder? I have very strong opinions in this area. If people feel that their life is in danger due to the fact that someone,or in this case,even more terrifying,a group of people have broke into their house,then how can this be viewed as murder? Yes,there was intent to harm by the householders but we do not yet know the circumstances surrounding this event.If I’d have been in that situation I’d have done anything to defend my family.I can’t think of anything more terrifying than to find  a burglar in my home.It is such a violation.In this day and age there are so many dangerous people about and even though I don’t condone violence in any way,shape or form I can’t say I wouldn’t react the same if I felt my family were at risk.I’d like to know more “facts” about the case before forming a fixed judgement.I hope the accomplice are found and punished accordingly.I also hope the householder’s that were arrested are treated and judged fairly.