A suspect known to Fijian police has been questioned over an alleged sexual assault of a Virgin Australia flight crew member amid ongoing investigations.

Fijian authorities were investigating allegations the crew member was assaulted while celebrating New Year’s Eve, and separately, that another crew member was robbed.

“These alleged incidents are regrettable,” Fiji’s deputy prime minister, Viliame R Gavoka, said in a statement.

“Our thoughts and concerns are with [the alleged victims] and for their health and wellbeing.”

Gavoka said a suspect known to police had been questioned over the alleged sexual assault.

The airline had sent support staff to Fiji amid reports three crew members were allegedly attacked while out clubbing in Nadi in the early hours of 1 January.

The crew members had since been confined to their hotel rooms near Nadi international airport, the Fiji Sun reported.

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Gavoka said reports of the crew being “detained” were “incorrect and false”.

“The crew, who are in good health, are being accommodated at a local hotel which is the nominated crew accommodation for layovers,” he said.

“The three crew members were also advised by their headquarters to remain within the hotel vicinity to ensure contactability and assist with police investigations.”

The crew members were expected to return home before the end of the week.

“Regrettably, incidents like [those alleged] can happen anywhere and Fiji is not immune,” Gavoka said.

“We, as always, remind tourists to exercise caution in nightclub areas and late at night.”

Fiji’s acting police commissioner, Juki Fong Chew, told the local newspaper that officers were investigating allegations of theft and assault.

The Flight Attendants’ Association of Australia’s federal secretary, Teri O’Toole, said it appeared the airline had acted very quickly and her union was ready to assist in any way.

However, she said the union was yet to receive any official approaches for assistance.

“I believe these crew were on what we would call an overnight, so they would get to Fiji, wait and [their] flight would leave the next day,” she told AAP.

O’Toole said there had been a lot of guesswork about what had happened and urged people not to speculate on the incident and respect the crew’s privacy during the police investigation.

“This is not a very common thing but it’s not something that’s never happened before, either,” she said. “It’s very disturbing for their friends and colleagues, everyone is very concerned for their welfare.”

The airline confirmed an incident took place, but no further details were provided on what happened.

Virgin staff had travelled to Nadi to provide support and family members of the affected crew were reportedly also flying to Fiji.

The Department of Foreign Affairs and Trade was aware of the reports but unable to provide further comment, a spokesperson said.

The Australian government advises people to exercise normal safety precautions when travelling to Fiji – the lowest of four official risk ratings.

“Crime in Fiji includes robbery, theft, violent assault, sexual assault and home invasions,” the Smart Traveller website states.

“Most crime is opportunistic. The highest risk is in urban areas and at night.”

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