One person has been confirmed dead from Ebola in an outbreak in a remote corner of northern Congo as health authorities look into a total of nine suspected cases, including another death, the country's health minister said.
One case of the haemorrhagic fever has been confirmed out of the five tested since the outbreak emerged in Bas-Uele province on April 22, Health Minister Oly Ilunga Kalenga said.
He said the confirmed case was of the Zaire strain of the virus.
The outbreak could test a recently developed experimental Ebola vaccine that the World Health Organisation (WHO) says could be used in emergencies.
The global vaccine alliance GAVI said 300,000 doses are available "if needed to stop this outbreak becoming a pandemic".
This vast, impoverished Central African nation has had seven known previous Ebola outbreaks, including one in 2014 with several dozen cases.
That outbreak was not connected to the massive epidemic in Guinea, Liberia and Sierra Leone that left thousands dead.
Dr Allarangar Yokouide, the WHO representative in Congo, said the first teams of specialists should arrive in the affected area of Likati on Friday or Saturday.
The zone is some 1,300 kilometres (800 miles) from the capital Kinshasa.
"The area in Likati is difficult to access, but the work of tracing contacts is very crucial to stopping the epidemic in its tracks," he said.
The community is near the border with Central African Republic.
Ebola occasionally jumps to humans from animals including bats and monkeys.
Without preventive measures, the virus can spread quickly between people and is fatal in up to 90% of cases.
There is no specific treatment for the disease.
The new cluster of Ebola cases will again test one of the world's least equipped health systems.
The US Agency for International Development has said an estimated 70% of the population has little or no access to health care.
"We urge you not to give in to panic," Mr Kalenga said.