A regional WHO official told The Associated Press that it was difficult to say how long work would be affected.

Confirmed Ebola cases have reached 202 in this outbreak, including 118 deaths.

Allied Democratic Forces rebels attacked Congolese army positions and several neighborhoods of Beni on Saturday and into Sunday, Capt. Mak Hazukay Mongha told the AP. The UN peacekeeping mission said its troops exchanged fire with rebels in Beni’s Mayangose area.

Angry over the killings, residents carried four of the bodies to the town hall, where police dispersed them with tear gas. While some health workers took refuge in a local hospital, the protesters destroyed a number of government buildings and blocked all traffic, Congo’s health ministry said.

Vehicles of aid organizations and the UN mission were pelted with stones, the UN-backed Radio Okapi reported.

The ADF rebels have killed hundreds of civilians in recent years and are just one of several militias active in Congo’s far northeast.

Another deadly attack last month in Beni forced the suspension of Ebola-containment efforts for days, complicating work to track suspected contacts of infected people. Since then, many of the new confirmed Ebola cases have been reported in Beni, and the rate of new cases overall has more than doubled, alarming aid groups.

Health efforts in recent weeks had started to show results, and this new attack “will bring us back,” Dr. Michel Yao, WHO’s incident manager for Ebola in North Kivu province, told the AP.

Work in Beni was suspended on Sunday and “tomorrow, we don’t know yet,” Yao said, noting that the burials of victims can be tense. “We understand. We are sympathetic. It’s not easy to lose relatives. At the same time, it could affect the (outbreak) response.”

The attack came after two medical agents with the Congolese army were shot dead by another rebel group — the first time health workers have been killed in this outbreak.

Congo’s health minister called it a “dark day” for everyone fighting Ebola.

Mai Mai rebels surged from the forest and opened fire on the unarmed agents with the army’s rapid intervention medical unit outside Butembo city, the health ministry said.

Health workers in this outbreak, declared on Aug. 1, have described hearing gunshots daily, operating under the armed escort of UN peacekeepers or Congolese security forces and ending work by sundown to lower the risk of attack.

Community resistance is also a problem, and Congo’s health ministry has reported “numerous aggressions” against health workers. Early this month, two Red Cross volunteers were severely injured in a confrontation with wary residents in a region traumatized by decades of fighting and facing an Ebola outbreak for the first time.

“Our agents will continue to go into the field each day to fulfill the mission entrusted to them,” Health Minister Oly Ilunga said. “They are true heroes, and we will continue to take all necessary measures so that they can do their job safely.”

On Wednesday, WHO said it was “deeply concerned” by the outbreak but that it does not yet warrant being declared a global emergency. An outbreak must be “an extraordinary event” that might cross borders, requiring a coordinated response. Confirmed cases have been found near the heavily traveled border with Uganda.

In the latest example of the rumors that pose another serious challenge to containing the virus, the health ministry said 22 young people in Butembo dug up an Ebola victim and opened the body bag to verify that health workers had not taken organs from the body.

They ended up touching highly infectious bodily fluids, the ministry said. “The next day, they agreed to be vaccinated,” joining the more than 20,000 people who have received vaccinations so far. (AP)