The head of the World Health Organization says attacks by armed groups in eastern Congo have killed workers responding to the Ebola outbreak.
He did not say how many people have been killed in the attacks in Biakato Mines and Mangina.
In his statement Thursday, Tedros Adhanom Ghebreyesus said: We are heartbroken that our worst fears have been realized.
The attacks come after days of deadly unrest in the city of Beni, where residents outraged by repeated rebel attacks stormed the local United Nations peacekeeping base.
Ebola response work was put on lockdown there, dismaying health experts who say every attack hurts crucial efforts to contain the deadly virus.
The number of cases had been dropping in the yearlong outbreak, the second-worst Ebola epidemic in history.