The handling of dead monkeys may be the source of the outbreak, the WHO suspects, according to Angop.

CNN: Ebola outbreak forces Angola to close Congo border

Angolan Health Minister Jose Van-Dunem announced the "suspension of migratory movements" at the country's north-eastern border Sunday, the Angop news agency reported.

CNN: Ebola outbreak forces Angola to close Congo border

The outbreak is centered in the western Kassi province of the Democratic Republic of Congo, which has been reporting intermittent cases of the disease since 1976, according to Angop.

CNN: Ebola outbreak forces Angola to close Congo border