The M23 rebels and the Congolese government traded accusations over responsibility as reports from the remote region began to emerge.
The collapse is one of the deadliest disasters in years in an area already facing a humanitarian crisis and ongoing conflict.
In May 2024, M23 seized the town of Rubaya and took control of its mines.
Here's what to know about the collapse:
Why did the accident happen?
On Wednesday, following heavy rains in eastern Congo, a network of hand-dug tunnels collapsed, killing at least 200 artisanal miners and trapping an unknown number who remain missing. The mine, located around 25 miles (40 kilometers) to the west of the regional capital of Goma, has been under the control of Rwandan-backed M23 rebels since early 2024 and employs thousands of miners who operate largely by hand.
Miners dig long tunnels, often parallel to one another, with limited support and no safe evacuation route in case of a collapse.
A former miner at the site told The Associated Press that there have been repeated landslides because the tunnels are dug by hand, poorly constructed, and not maintained.
“People dig everywhere, without control or safety measures. In a single pit, there can be as many as 500 miners, and because the tunnels run parallel, one collapse can affect many pits at once,” former miner Clovis Mafare said.
Congo’s government, in a statement on X, expressed solidarity with the victims’ families and accused the rebels of illegally and unsafely exploiting the region’s natural resources. An M23 spokesperson accused the government of politicizing a “tragic accident” and provided a list of other collapses at government-controlled mines.
What is happening in eastern Congo?
The M23 group is one of about 100 armed factions vying for a foothold in eastern Congo, where a decades-long conflict has raged.
Since early last year, the M23 rebel group has been on the offensive, taking the regional capitals of Goma and Bukavu and advancing toward the south of the country. The group, composed primarily of fighters from the Tutsi minority who failed to integrate into the Congolese army, launched an insurgency against the Congolese government in 2012. It was then dormant for a decade, until its resurgence in 2022.
M23 claims to defend Tutsis and Congolese of Rwandan origin from discrimination. Critics say it’s a pretext for neighboring Rwanda to obtain economic and political influence over eastern Congo.
Congo, the United States, and U.N. experts accuse Rwanda of backing the M23, which had hundreds of members in 2021. Now, according to the United Nations, the group has around 6,500 fighters.
While Rwanda denies that claim, it acknowledged last year that it has troops and missile systems in eastern Congo, allegedly to safeguard its security. U.N. experts estimate there are up to 4,000 Rwandan forces in Congo.
Why is Rubaya important?
The Rubaya mines have been at the center of the fighting, changing hands between the Congolese government and rebel groups. For over a year now, the site has been controlled by the M23 rebels.
The mines produce coltan — short for columbite-tantalite — an ore from which the metals tantalum and niobium are extracted. Both are considered critical raw materials by the United States, the European Union, China, and Japan. Tantalum is used in mobile phones, computers, and automotive electronics, as well as in aircraft engines, missile components, and GPS systems. Niobium is used in pipelines, rockets, and jet engines.
According to a U.N. report, since seizing Rubaya, the M23 has imposed taxes on the monthly trade and transport of 120 metric tonnes (118 tons) of coltan, generating at least $800,000 a month. The coltan is then exported to Rwanda, U.N. experts said. But even before M23 seized control of the mine, analysts said that the mineral was sold to Rwanda, the only difference being that it was done through Congolese intermediaries.
Experts say it is not easy to trace how coltan reaches Western countries because of a murky supply chain.
How is the United States involved?
The Trump administration hosted the leaders of Rwanda and Congo in December and oversaw the signing of a peace deal that critics say has done little to slow the fighting.
Lauded by the White House as a “historic” agreement brokered by Trump, the pact followed monthslong peace efforts by the U.S. and partners, including the African Union and Qatar, and finalized an earlier deal signed in June.
The region of eastern Congo, rich in critical minerals, has been of interest to Trump as Washington seeks ways to circumvent China to secure rare earths. China accounts for nearly 70% of the world’s rare earth mining and controls roughly 90% of global rare earths processing.
The National Energy Emergency executive order, issued by Trump, highlighted the significance of critical minerals — including tantalum and niobium — and called for securing U.S. access to ensure both “modern life and military preparedness.”