The family of a missing Chinese student are praying she is a victim of kidnapping rather than drowning.

"That way, at least there is hope that she may be still alive," a family member of Yue Gui told Chinese media.

Ten police divers yesterday continued the search for the 30-year-old PhD student from Beijing, also known as Alice, who is thought to have fallen into the sea while checking the water temperature.

She was last seen at 11pm Saturday at her residence at the Leigh marine laboratory, which is run by the University of Auckland.

Miss Yue's normal Sunday morning routine involved her checking the water temperature at the Goat Island Marine Reserve.

But police fear she may have fallen into the water because weather and tidal conditions were rough at the time.

An acquaintance of Miss Yue, who did not wish to be named, told the Herald she had been looking forward to returning to China after completing her postgraduate project studying the feeding biology of young greenshell mussels.

"Yue Gui is a city girl, but she loved the sea and spends more than half her life on the water rather than on land," she said.

"She does not have much of a social life or many human friends but Yue Gui sees the fish and other living creatures in the ocean as her friends."

Online postings in response to Chinese news reports about the missing woman described her as a competent swimmer; some expressed hope that her swimming skills would keep her alive.

A university spokesman said Miss Yue's classmates were "naturally upset". Seven of them joined the search of the coastline towards Pakiri.

Police are seeking information from anyone who may have seen Miss Yue from Saturday evening onwards.

Sergeant Bede Haughey, of Warkworth police, said there was a 4-5m tide through the area on Sunday morning leading police to speculate she had been swept away.

It was not until that afternoon that it was noticed she was missing, as was the water temperature-measuring apparatus, while all her belongings were still in her room.

Mr Haughey had spoken to her next-of-kin and they were coming from China.

"They were quite traumatised but they're hopeful that there will be a positive outcome to the search, but they're aware that as time progresses the chances of Alice being found alive diminish."

The search will resume this morning.

- additional reporting: NZPA