Hundreds of doctors protested in the eastern DR Congo city of Beni on Monday and declared a three-day hospital stoppage after health facilities were struck in a deadly attack blamed on the notorious ADF militia.

One of the most ruthless of the scores of armed groups that roam the region, the ADF -- Allied Democratic Forces -- is described by the Islamic State group as its affiliate in central Africa.

Suspected ADF assailants last Wednesday torched a health centre in Maboya and a nearby hospital, killing seven people, including Sylvie Kavuke, a nun who also worked as a doctor.

Demonstrators carrying signs reading "Doctors are outraged' and demanding the rebuilding of the facilities marched to city hall and read out a statement, outlining a string of atrocities and kidnappings of medical staff in recent years.

They demanded heightened security at medical sites, a bonus for working in areas of risk, and the right for security guards to bear arms in dangerous "red zones".

Godefroid Mbeho, head of the Beni doctors' association, said doctors would boycott working at hospitals over the next three days in order to press their demands.

The ADF has been blamed for thousands of deaths in the Beni area, the epicentre of violence in troubled North Kivu province.

Denis Mukwege, who won the 2018 Nobel Peace Prize for his pioneering work with rape victims in neighbouring South Kivu, issued a statement on Sunday saying "hospitals should never be a target and healthcare workers and patients should always be protected."

"These odious crimes cannot remain unpunished," he said. "Justice is crucial... for preventing the repetition of mass atrocities that have caused grief for every Congolese family for more than a quarter of a century."