The seven people hospitalised in Fiji with suspected severe alcohol poisoning are reported to be in a stable condition, Tourism Fiji chief executive Brent Hill says.
However, Fiji's health boss said two remained in a critical condition.
Seven people, including four Australian tourists and one American, and two other foreigners who live in Fiji, had been drinking cocktails at the 5-star Warwick Resort in the Coral Coast before they fell ill.
All have now been transferred to the larger Lautoka Hospital from Sigatoka Hospital because of the severity of their condition.
Hill told RNZ Pacific they are all now in a stable condition and there had been improvement in some symptoms.
"We don't want to speculate on exactly the cause; we don't know that yet," he said.
"But what we do know is that it was limited to only seven tourists at one resort and only at one bar in that resort as well.
"Talking to the management they're quite perplexed as to how it's happened, and certainly there are no accusations around that something's been put into their drink or been diluted or using a foreign substance."
A resort guest, who did not want to be named, told RNZ Pacific that his friend, a local, was having seizures on Saturday afternoon and is still to ill to get up.
The guest said he was certain the drinks had been tampered with.
"We have not received any proper communication from the Warwick team and [they] just asked one of my friends to sign an indemnity form."
He said that he and the group that he was with had all had one drink each at the adult pool bar.
"Everyone that I saw at the Sigatoka Hospital all drank the piña colada.
"The hospital and doctors were the saving grace...they were really overwhelmed, but tried their best to get everyone stable and moved out to Lautoka ICU overnight."
Fiji's Health Secretary Dr Jemesa Tudravu told local media two out of the seven affected individuals had been placed on life support over the weekend. However, they have since recovered and remain in critical condition.
Tudravu said all those affected were tourists, and no locals were involved.
But the resort guest who spoke to RNZ Pacific claims that Tudravu has completely ignored the fact that locals were also affected.
A Fiji police spokesperson said on Monday that a 26-year-old local woman had been discharged from Sigatoka Hospital.
"Others have been transferred to Lautoka Aspen Hospital and we will wait for medical authorities to clear the victims first before we can interview them," he said.
"But police investigation is already underway."
Hill said the tourism industry was very conscious of the recent tainted alcohol incident in Laos, where several people died, but said it's "a long way from that".
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"The resort has certainly given us assurance that there's no indication around substituting substances in beverages and so on. So it's a little bit of a mystery that a nice resort would experience something like this."
When asked if tourists needed to be careful ordering cocktails in Fiji, Hill said people needed to be careful anywhere around the world, including at home.
"The risk is very, very small, but at the same time, we don't want to diminish for these seven people.
"It's obviously been a really unfortunate experience and we certainly are trying to work out what's caused that and our investigation is continuing."
Brent said he has never heard of anything like this happening in Fiji before.
He hoped it would not affect Fiji's reputation as a tourist destination.
"I do understand, of course, based on recent events in Southeast Asia that people want assurance that they can be safe, and certainly from our perspective it's a really isolated case."
A spokesperson for Warwick Fiji told RNZ Pacific that they have "nothing to disclose".
RNZ Pacific was told the general manager of the high-end resort will not front for an interview because the suspected poisoning was still under investigation.