That is really scary! Glad everything is ok and your alarm was working perfectly!
I've had something big and expensive stolen from me not to long ago. MY BRAND NEW CAR!!! It was replaced but I know you had something more precious to worry about, and I'm glad they're fine!!
Sometimes desperate people do desperate things. It's in no way an excuse or a justification for what they did though.
I wouldn't say "immigrants" did it though, this whole country is built on immigrants....I'd just say desperate people.