The Ebola outbreak in the Democratic Republic of Congo has reached 5,000 cases, government data showed Wednesday, as responders warn the virus is spreading at an unprecedented speed that is outpacing efforts to contain it in one of the country's most remote regions.

Data from Congo's Ministry of Health showed the outbreak had recorded 5,021 cases, including 2,378 deaths, as of Sunday. The crisis is unfolding under some of the most challenging conditions imaginable, driven by insecurity, displacement and intense population movement.

The outbreak has infected and killed more people at a greater speed than any other Ebola outbreak in history.

Starting from the first detected case, it has spread approximately three times faster than the 2014-2016 outbreak across West Africa, which remains the deadliest Ebola outbreak on record with more than 11,000 deaths.

The outbreak "has spread rapidly and the risk of further national and international spread remains high," World Health Organization Director-General Tedros Adhanom Ghebreyesus said Tuesday at a meeting convened by the agency.

"We must be frank: the epidemic is far from being under control," he added.

Safety concerns have severely limited the response. Health workers are being targeted, particularly in Ituri province, which has been the hardest-hit area of the outbreak.

On Monday, residents attacked a health team in the territory of Aru after a suspected case was reported there. A mob set fire to an ambulance and damaged two other vehicles, according to Michael Wani, president of the Union of Cultural Associations for the Development of Ituri.