A total of 93 cases of Ebola have been confirmed in the last four days in the Democratic Republic of Congo, an average of more than 23 a day, a humanitarian agency has said.
A record 27 cases were reported on Monday – more than double the previous record of 13 in a single day, the International Rescue Committee (IRC) added.
The agency said all but essential medical operations have been halted for more than a week in the Ebola flashpoints of Butembo and Katwa in the east because of security concerns.
Ebola treatment centres have been attacked by armed groups, and a Cameroonian doctor was killed on 19 April.
Eastern DR Congo is mostly lawless. Some people also have superstitious beliefs about Ebola, and accuse foreigners of bringing it to the country.