Tributes are flowing for a Tauranga woman as police investigate the circumstances of her death.

Melanie Floyd, who grew up in Tauranga and went to Otumoetai College, succumbed to severe head injuries in the Royal Brisbane and Women's Hospital on Saturday after her family made the decision to switch off life support.

Former Otumoetai College student Melanie Floyd died of severe head injuries in an Australian Hospital.

The 28-year-old's death came four days after her boyfriend, 24, called emergency services to her home, saying he woke up to find her unconscious on her bed.

She was admitted to hospital with minor bruising to the face, but her brain was swollen.

The man has since refused to co-operate with police, who are now treating the case as a murder investigation.

Otumoetai College teacher and head of girls volleyball Stewart Henderson was "gob-smacked" when he heard the news.

Melanie played volleyball throughout her high school years as a setter and Stewart got to know her and her family, who were all involved in the sport.

"It's very difficult to talk about for one so young to have died like this," Stewart says.

Her cousin Kylie Rae-Bidois, who played volleyball for New Zealand in the 1990's, called Stewart just before leaving for Brisbane to tell him the news.

"She was just a loving personality, she was really friendly and got on so well with everybody ... It's a huge blow to our [volleyball] family.

"In the past couple of days, I have seen a lot of glowing tributes to her on Facebook. She deserved every one of them."

Friend Mandy Onassis, who met Melanie when they worked at Brisbane bar The Met in 2010, described Floyd as one of the nicest people someone could meet.

"She was a vibrant, strong and very popular person, very good at her job, well respected, everybody loved her," Onassis said.

"I don't know of anyone who didn't absolutely enjoy her. She was very awesome to hang out with."

Onassis has started a Go Fund Me page, which had raised over $12,000 by Monday afternoon, to help Floyd's family with the costs associated with her death.

A post-mortem was due to be completed on Monday, a Queensland Police spokesman said, and police hoped they would have further insight into what happened when the results were known.

​Police had spoken to her partner of 18 months because he was so close to her, not necessarily because he was a suspect, the spokesman said.

"He didn't say much."

- Audrey Malone, Stuff.co.nz