Three Red Cross volunteers died in the Democratic Republic of Congo from suspected Ebola likely caught while managing dead bodies, the organisation has said.

They are believed to have contracted Ebola on 27 March while working in the eastern region of Ituri on a project unrelated to the virus, before the outbreak was identified.

The volunteers are among the first known victims of DR Congo's Ebola outbreak, which has resulted in more than 170 suspected deaths and 750 suspected cases.

The International Federation of Red Cross and Red Crescent Societies (IFRC) said they had died after serving their communities "with courage and humanity".

Alikana Udumusi Augustin, Sezabo Katanabo and Ajiko Chandiru Viviane had been working in the town of Mongwalu, which is now considered the epicentre of the outbreak. They died between 5 and 16 May.

Health experts warn the bodies of Ebola patients can spread the virus because bodily fluids remain highly infectious after death.

The outbreak involves a rare species of Ebola, known as Bundibugyo, which has no proven vaccine and kills about a third of those infected.

On Friday, the World Health Organization (WHO) raised the public health risk from the virus in DR Congo from "high" to "very high".

WHO chief Dr Tedros Adhanom Ghebreyesus also said the risk in the wider region in Africa was high but remained low globally.

The country's neighbour Uganda confirmed three new cases on Saturday, bringing its total infections to five, while the African Centres for Disease Control warned 10 other countries on the continent were at risk from the outbreak.

It named Angola, Burundi, the Central African Republic, the Republic of Congo, Ethiopia, Kenya, Rwanda, South Sudan, Tanzania and Zambia.

Meanwhile, DR Congo suspended all commercial and private flights to and from Bunia - the provincial capital of Ituri, where most cases and deaths have been reported - to curb "cross-border spread".

"Humanitarian, medical or emergency flights will only be authorised after special approval from the aviation and health authorities," the country's transport ministry said in a statement.