The statement late Friday said the confirmed cases are in Mbandaka city, where a single case was confirmed earlier in the week.
There are now 17 confirmed Ebola cases in this outbreak, including one death, plus 21 probable cases and five suspected ones. It was not immediately clear what link the new cases might have to others.
The World Health Organization on Friday decided not to declare the outbreak a global health emergency, but it called the risk of spread within Congo "very high" and warned nine neighboring countries that the risk to them was high. WHO said there should be no international travel or trade restrictions.
The outbreak is a test of a new experimental Ebola vaccine that proved effective in the West Africa outbreak a few years ago. Vaccinations are expected to start early in the week, with more than 4,000 doses already in Congo and more on the way.
A major challenge will be keeping the vaccines cold in the vast, impoverished country where infrastructure is poor.
While Congo has contained several Ebola outbreaks in the past, all of them were based in remote rural areas. The virus has twice made it to Congo's capital of 10 million people, Kinshasa, in the past but was rapidly stopped.
CNBC
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