Her extended family in Auckland and Whangarei have gathered to support her mother and three teenaged siblings.
The family lost their father a few years ago in a forestry accident in Australia.
Cousin Kelly Gillard, of Auckland, said the family were devastated at the news.
"We're just shattered," Ms Gillard said through tears.
"She was such a beautiful girl and she loved her family and friends. There was nothing wrong with her at all. We're just at a loss, we don't know what's happened."
Miss Hammond attended Whangarei Girls High School.
She moved to Melbourne recently and had been working in an administration job at a law firm.
Miss Hammond's mother, Cindy Lomas, had become worried when phone calls and text messages to her daughter went unanswered.
The family are now fundraising to bring the body back home. Click here for more details.