Samoa has halted a vaccination programme as officials probe the sudden death of two infants.
Samoan health officials have recalled a vaccine as they investigate the deaths of two babies shortly after immunisation.
The one-year-olds both died after being given a measles, mumps and rubella (MMR) vaccine at the district hospital in Savai'i last Friday, according to the country's government.
The vaccines would be immediately recalled and the immunisation programme paused while the deaths were probed, Director General of Health Leausa Take Naseri told reporters.
Police are looking into the matter, and Dr Naseri said the nurses involved had been moved for their own safety.
Prime Minister Tuilaepa Aiono Sailele Malielegaoi, in a statement, called for a full inquiry.
"There are already processes that will determine if negligence is a factor," he said.
"And if so, rest assured those processes will be implemented to the letter to ensure that such a tragedy will not be repeated and those responsible will be made to answer."