Residents of a town at the epicenter of the Ebola outbreak in eastern Congo attacked and burned part of a health center where people are being treated for the virus, and 18 people suspected of infection left the facility, a local hospital director said Saturday. It was the second such attack in the region in a week.

Unidentified people arrived at the clinic in Mongbwalu on Friday night and set fire to a tent set up for suspected and confirmed Ebola cases by the Doctors Without Borders humanitarian group, Dr. Richard Lokudi, director of the Mongbwalu General Reference Hospital, told The Associated Press.