An American tourist and two foreign residents of Fiji are among a group of seven who fell ill after drinking cocktails at a resort.
Four Australians remain critically ill in hospital with suspected alcohol poisoning.
The ABC reported one of the Australians, a 56-year-old woman, was under constant surveillance in hospital while a 19-year-old was experiencing serious medical episodes. Two other Australian women, aged 49 and 18, were understood to be in critical condition but not as seriously ill.
RNZ has contacted the Ministry of Foreign Affairs and Trade about whether any New Zealanders have been involved.
Fiji journalist Mereoni Mili said health ministry inspectors and police were still investigating, and it wasn't yet known exactly what caused the illness.
"We just know they had cocktails at the bar at the resort," she told Morning Report.
The four in critical condition were at Lautoka Hospital, some three and a half hours away from the popular Warwick Resort they were staying at on the Coral Coast.
"That's the last we heard from the Ministry of Health and Medical Services last night."
An update was expected later on Monday.
Mili said the suspected alcohol poisoning was a huge worry for authorities.
"Knowing our economy that relies heavily on tourism this will be a worry not only for the authorities but also for stakeholders of the tourism industry. They will be taking precautionary measures I believe to ensure this does not escalate."
The suspected poisoning comes just weeks after methanol poisoning in Laos killed two Australian teenagers, a British national, an American and two Danish women. They were reported to have drunk alcohol in the popular tourist town of Vang Vieng.
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