I was visiting Darwin, NT, Australia a few years back and I encountered this bird. I must say it was in Darwin's Botanical Gardens, so I can't be absolutely positive the Northern Territory is its original habitat. However, I'm pretty sure it's a NT native, as the whole Gardens were packed with, and dedicated to NT's wildlife.
The photo is kind of dark and a bit fuzzy due to poor lighting conditions. I already tried to digitally enhance it by removing shadows and so forth.
I tried Google Images reverse search to ID this bird, but I'm not a hero with that tool. Although it looks a bit like it - it's definitely not a Jabiru.