 A crash of this nature involving this many people is a very significant and a very tragic incident. Superintendent Graham Payne, he says the extent of the crash is so big investigators can't even begin to work out what went wrong. We haven't determined any factors that have contributed to the crash at this stage. It's feared the death toll will rise with 27 people injured, some reported to be critical with life-threatening injuries. Scott Maimon for CBS News, Canberra, Australia.