As M23 rebels continue to gain ground in South Kivu in the eastern Democratic Republic of the Congo (RDC), the country's top UN humanitarian official has told UN News that increasing "complexity and needs" are fuelling a crisis which had already left more than a million people displaced before the latest surge in fighting.
"The frontline is getting closer to Kavumu Airport," warned Bruno Lemarquis on Wednesday.
Following the fall of regional capital Goma, in North Kivu, at the end of January, the Rwanda-backed M23 armed group is now making headway against Congelese Government forces towards Bukavu, the capital of South Kivu.
Kalehe, a major city in the province, fell around midday on Wednesday local time, the Humanitarian Coordinator reported. The city is only 20 miles away from Kavumu, which is home to the province's main airport.
The commercial airfield - a 20 mile drive from Bukavu - is mainly being used for military operations by Kinshasa's beleaguered regular forces.
"Until recently, it was our main lifeline for bringing personnel to South Kivu," said Mr. Lemarquis.
But as with the Goma airport, which remains non-operational, that window has now closed.
A historically dire situation
Before the M23's latest offensive at the beginning of the year, Mr. Lemarquis recalled that the humanitarian situation in South Kivu was already dire.
Roughly 1.65 million people, or just over 20 per cent of the province's population, had been displaced for a wide range of reasons.
"There are other conflicts in the province, community tensions, tensions related to land," he explained.
South Kivu is also prone to natural disasters, including landslides on the shores of Lake Kivu, which are responsible for many displacements.
"So, we had a major humanitarian operation running in South Kivu," said Mr. Lemarquis.
The recent advances of the M23 rebels, whose incursion in South Kivu is the first since the withdrawal of the UN Stabilization Mission in the DRC ( MONUSCO ) from the province in June 2024, are compounding historic problems.
"This will only add complexity and needs," the Human Coordinator said.
At least 170,000 new displacements
Mr. Lemarquis estimated that the recent clashes in the province had displaced at least 170,000, a figure that does not include estimates for the past two weeks.
The Humanitarian Coordinator also noted an influx of people moving towards Bukavu, where nearly 1.3 million people already reside.
"Depending on how the situation evolves, in the coming days, we can imagine that there will be an even larger influx of population towards the city of Bukavu, then out of the city, towards the South," he explained.
Such an outcome, he added, would hinder vulnerable people' access to health and social services.
Risks of epidemics
Mr. Lemarquis also voiced concern over the spread of infectious diseases as fighting continues in South Kivu, a province rife with cholera.
"When essential services are impaired, this can lead to epidemic outbreaks," he warned.
This is especially worrisome, he added, because the province is currently the global epicentre of a new mpox strain, known as clade 1b, which is particularly prevalent around Kalehe, the city now controlled by M23.
No humanitarian access to the South
On a positive note, the Humanitarian Coordinator said that the road from Goma to Minova, the first South Kivu town conquered by the M23 in mid-January, is no longer closed.
"There were a few rather difficult days for our humanitarian colleagues because of the fighting," he acknowledged. "But now access has been restored."
Further South in the province, however, humanitarian access has been cut off.
"For quite some time, the road between Goma and Bukavu has not been accessible," he said.
Alternative pathways, including via Lake Kivu, which borders the province and connects Goma in the north to Bukavu in the south, have also been cut off.
"There aren't many alternative routes, the airport being the main access route," he acknowledged.