Health officials in New Caledonia have discovered the presence of the type of mosquito which can carry malaria.
But the officials say there is no risk to the public because the parasite that triggers the disease is not present in the territory.
It is not known when and how the Anopheles mosquitoes entered New Caledonia but they are now established in the area of La Tontouta, north of Noumea.
Malaria is found in other parts of Melanesia.
Reports say the mosquitoes were found during checks as part of efforts to fight dengue fever.
Another mosquito type, the Aedes aegypti, has been a major health concern in New Caledonia, having spread dengue and Zika.
Plans have been drawn up to introduce the Wolbachia bacteria which should prevent that mosquito from being able to pass on the diseases.