Behind our everyday tech lies a supply chain tainted by violence
Somewhere between the mine and the marketplace, accountability dissolves. A year-long investigation by Global Witness has traced the coltan inside the world's most familiar electronics back to militia-controlled mines in the Democratic Republic of the Congo, where the M23 armed group funds mass atrocities through a monthly tax on extraction. The systems built to prevent exactly this — industry traceability schemes, corporate due diligence, certification bodies — appear to have failed quietly and at scale, leaving consumers and companies alike entangled in a supply chain that finances violence.
- M23 controls 15% of the world's coltan reserves at Rubaya, generating roughly £600,000 a month to bankroll killings, mass displacement, and sexual violence across eastern DRC.
- Smugglers move conflict coltan through Rwanda and into smelters in China and Kazakhstan, where it vanishes into certified supply chains and resurfaces in phones, laptops, and electronics sold worldwide.
- The certification schemes designed to stop this — ITSCI and RMI — failed to detect the tainted mineral, exposing a structural gap between compliance paperwork and ground-level reality.
- Amazon, Ericsson, Sony, and Vodafone have each acknowledged the findings with varying degrees of concern, but none has yet committed to halting Rwandan coltan purchases.
- Global Witness is calling for companies to suspend all Rwandan coltan sourcing until M23 withdraws from the mines, and for governments to impose sanctions on those financing the militia's occupation.
The coltan inside your smartphone is essential to how it works — and nearly impossible to trace. A year-long Global Witness investigation has found that major technology companies, including Amazon, Ericsson, and Sony, have in all likelihood sourced coltan from mines in the DRC's North Kivu province now controlled by the M23 militia. Since seizing the Rubaya mining complex two years ago, M23 has levied a tax on every kilogram extracted, generating an estimated £600,000 monthly. That revenue funds an occupation marked by mass killings, the displacement of hundreds of thousands of civilians, and widespread sexual violence. Rwanda, which denies backing M23, has thousands of troops operating alongside the militia inside DRC territory.
The mineral's journey from conflict zone to consumer product runs through smugglers, middlemen, and smelters in China and Kazakhstan, where it is refined into tantalum and processed into capacitors. Global Witness found that five of the seven largest Rwandan mineral exporters purchase conflict coltan from DRC mines, and that large quantities now flow through Goma — the border city M23 captured last year — making detection harder than ever.
What compounds the scandal is that the systems built to prevent it have quietly collapsed. Both the International Tin Supply Chain Initiative and the Responsible Minerals Initiative are designed to keep conflict minerals out of global supply chains, yet neither detected the Rubaya coltan. When confronted, the named companies offered measured responses: Amazon pledged to request additional due diligence from implicated suppliers; Ericsson acknowledged the difficulty of multi-tier oversight while noting two flagged smelters appear in its supply chain; Vodafone deferred to the certification bodies it relies upon.
Global Witness has called on international companies to stop purchasing Rwandan coltan entirely until M23 withdraws from the mines, and on governments to impose sanctions on those whose financial activity sustains the militia. The investigation leaves a stark question unanswered: if certification schemes fail, corporate pledges ring hollow, and the violence continues, who is finally responsible for what ends up on the shelf?
The smartphone in your pocket likely contains a mineral called coltan. It's essential—a component in the capacitors that make modern electronics work. But tracing where that coltan came from is nearly impossible, and a year-long investigation by Global Witness suggests that major technology companies including Amazon, Ericsson, and Sony have probably acquired it from mines controlled by a militia accused of mass killing, sexual violence, and torture.
The M23 militia seized control of the Rubaya mining complex in the Democratic Republic of the Congo's North Kivu province two years ago. Rubaya sits atop roughly 15 percent of the world's coltan reserves. Since taking the mines, M23 has charged a tax on every kilogram extracted—generating approximately £600,000 each month, according to estimates by the UN's group of experts. That money funds the militia's occupation of eastern DRC, where it has killed thousands of people, displaced hundreds of thousands more, and committed widespread rape and abduction. Rwanda denies backing M23, though up to 7,000 Rwandan troops operate within the DRC alongside the militia.
The coltan doesn't stay in the Congo. Global Witness interviewed smugglers and found that five of the seven largest Rwandan mineral exporters purchase conflict coltan from DRC mines. The mineral then moves through middlemen to smelters in China and Kazakhstan, where it is refined into tantalum and processed into the capacitors that end up in phones, computers, and other electronics sold globally. Much of this smuggling once happened through lightly monitored border crossings, but sources told Global Witness that large quantities now flow through Goma, the DRC border city that M23 captured last year.
What makes this discovery particularly troubling is that the systems designed to prevent exactly this scenario appear to have failed. The International Tin Supply Chain Initiative, known as ITSCI, is supposed to ensure that minerals entering global supply chains are sourced responsibly and don't finance conflict. The Responsible Minerals Initiative, or RMI, serves a similar function. Yet Global Witness found that these traceability schemes have largely failed to detect coltan from the Rubaya mines. The investigation reviewed trade data and cross-checked customs records, revealing how due diligence systems have broken down at multiple points in the supply chain.
When contacted, the companies responded with varying degrees of acknowledgment. Amazon said it doesn't source minerals directly from mines or smelters but committed to requesting additional due diligence from suppliers connected to the smelters identified in the report. Ericsson stated it takes the allegations seriously and noted that tantalum enters its supply chain through multiple tiers of suppliers, making oversight difficult. The company said it had reviewed named smelters against its supplier data and found two that appear in its supply chain and are listed as RMI-conformant, though it acknowledged that RMI compliance alone doesn't constitute complete due diligence. Vodafone argued that as a telecommunications operator, it doesn't manufacture products or purchase minerals directly, and therefore relies on certified organizations like RMI to verify sourcing.
Alex Kopp, a senior policy and advocacy adviser at Global Witness, framed the problem starkly: behind the everyday technology people use lies a supply chain tainted by violence, exploitation, and human suffering. He called for government intervention to hold companies accountable and for sanctions against those whose financial activities enable M23's brutal occupation. Global Witness urged international companies to stop buying coltan from Rwanda entirely until M23 withdraws from the Rubaya mines, unless they can thoroughly verify the mineral's origin through direct inspection before export.
The investigation exposes a gap between corporate responsibility claims and supply chain reality. Companies say they care about ethical sourcing. Certification schemes exist to verify it. Yet coltan mined by a militia committing atrocities, taxed to fund those atrocities, and smuggled across borders continues to flow into the products that sit on store shelves and in people's homes. The question now is whether the companies named will take action, and whether governments will force them to.
Notable Quotes
Behind our everyday tech lies a supply chain tainted by violence, exploitation and human suffering.— Alex Kopp, Global Witness senior policy and advocacy adviser
The companies behind our phones, computers and cars haven't been able or willing to clean up their supply chains. This fuels instability and prolongs the suffering of communities.— Alex Kopp, Global Witness
The Hearth Conversation Another angle on the story
Why does coltan matter so much that a militia would fight to control these mines?
It's not just valuable—it's essential. Coltan becomes tantalum, which goes into capacitors. You can't make modern electronics without it. Rubaya alone holds about 15 percent of the world's supply, so controlling it means controlling a chokepoint in global manufacturing.
And M23 is making money from this?
About £600,000 a month, according to UN estimates. That's not incidental revenue—that's the fuel for their entire occupation. The militia uses that money to pay soldiers, buy weapons, maintain control of the territory. The mining tax is how they sustain the violence.
So when I buy a phone, I'm potentially funding atrocities?
Potentially, yes. But unknowingly. The companies don't know where the coltan came from. It gets smuggled from the DRC into Rwanda, sold to middlemen, shipped to smelters in China or Kazakhstan, processed, and then sold to manufacturers. By the time it reaches a company like Amazon or Sony, the origin is obscured.
Aren't there systems to prevent this?
There are supposed to be. ITSCI and RMI are certification schemes designed to keep conflict minerals out of supply chains. But Global Witness found they've largely failed. The schemes can't detect coltan from Rubaya, or they're not being applied rigorously enough.
What did the companies say when confronted?
They said they take it seriously and don't source directly from mines. But they also admitted they can't fully trace where minerals come from once they enter the supply chain through multiple tiers of suppliers. It's a convenient gap—they're not lying, but they're also not looking too hard.
What happens next?
Global Witness is calling for companies to stop buying from Rwanda entirely until M23 leaves. But that requires political will and consumer pressure. Right now, the incentive to maintain cheap supply chains is stronger than the incentive to verify where minerals come from.