Attacks on Ebola treatment centers in eastern Democratic Republic of Congo underscore the growing challenges authorities face, including rising community resistance, as they work to contain an outbreak declared a global health emergency.

Congolese authorities said Sunday that suspected cases have surpassed 900 in the country’s east, mostly in Ituri Province, the epicenter of the outbreak. Later that night, angry young men stormed an Ebola treatment hospital in Mongbwalu, according to the hospital director.

The attackers were demanding the release of two relatives’ bodies, said Dr. Richard Lokudu. Medical staff evacuated patients as gunfire erupted nearby, and it was not immediately clear whether anyone was injured.

The assault, along with arson attacks on two health centers last week in the outbreak’s core region, underscores rising tensions in an area long destabilized by armed rebel violence, mass displacement, weak governance and aid cuts that have strained already fragile health services.

"A devastating set of emergencies are converging,” said the Physicians for Human Rights nonprofit.

Here is a look at the longstanding crises in eastern Congo that have made it home to one of the world’s worst humanitarian disasters and how they are affecting the response to a rare type of Ebola.

Eastern Congo has for years seen attacks by dozens of rebel and terrorist groups, some with links to foreign countries or the Daesh group.

The Rwanda-backed M23 rebels control parts of the region. While the Congolese government still largely controls northeastern Ituri Province, the epicenter of the Ebola outbreak, that control is tenuous.

The Allied Democratic Forces, a Ugandan terrorist group linked to Daesh, is one of the dominant rebel groups there and is responsible for violent attacks against civilians.

Before the outbreak, Doctors Without Borders said in an assessment that insecurity in Ituri had worsened, forcing doctors and nurses to flee and leaving overwhelmed health facilities and, in some areas, "catastrophic conditions.”

The U.N. humanitarian office says nearly 1 million people have been displaced from their homes by conflict in Ituri.

That means the Ebola outbreak is "unfolding in communities already facing insecurity, displacement and fragile health care systems,” said Gabriela Arenas, a regional coordinator at the International Federation of Red Cross and Red Crescent Societies.

There are concerns the disease could spread to large displacement camps near the city of Bunia, where the first cases were reported.

The Congolese Ministry of Communication said on X on Sunday that there were 904 suspected Ebola cases, mostly in Ituri, a sharp increase from the previously reported figure of more than 700.

The ministry also said suspected Ebola deaths stood at 119, but regional totals released separately added up to 220. Officials could not immediately be reached to explain the discrepancy.

Cases have also been reported in two other eastern provinces, North Kivu and South Kivu, where the M23 rebels also operate, as well as in neighboring Uganda.

As a result, the outbreak in Congo is being managed by the government and, in some areas, by rebel authorities, with support from aid agencies.

Health experts say international aid cuts last year by the United States and other wealthy nations have had a severe impact in eastern Congo, given its overlapping crises.

The cuts "reduced the capacity to detect and respond to infectious disease outbreaks,” said Thomas McHale, public health director at Physicians for Human Rights. Congo has had more than a dozen previous Ebola outbreaks.

Aid groups on the ground say they lack basic equipment, including face shields, protective suits, testing kits and body bags needed for safe burials of highly contagious victims.

"We have made requests to different partners, but we have not yet really received anything,” said Julienne Lusenge, president of Women’s Solidarity for Inclusive Peace and Development, which operates a small hospital near Bunia.

"We only have hand sanitizer and a few masks for the nurses,” she said.

The Bundibugyo strain of Ebola virus responsible for the outbreak has no approved vaccine or treatment.

Colin Thomas-Jensen, director of impact at the Aurora Humanitarian Initiative, said attacks on health facilities treating Ebola may reflect deep public skepticism and anger in eastern Congo over years of violence, weak state protection and limited effectiveness of international peacekeeping efforts.

Another source of anger has been strict burial protocols for suspected Ebola victims, which authorities enforce to prevent transmission from traditional funerals where bodies are prepared and mourned in close contact.

Authorities in northeastern Congo have banned funeral wakes and gatherings of more than 50 people, and armed police and soldiers are guarding some burials conducted by aid workers.