MMG (HKG: 1208), the China-controlled miner and subsidiary of state-owned China Minmetals Corp., has suspended operations at its Las Bambas copper mine in Peru after a workplace accident killed two workers, adding a further disruption to South American copper supply at a time when concentrate availability remains tight.

The accident occurred on Aug. 18 during pump replacement work at a clarification pond located about 9 km from the processing plant, killing two workers and injuring three others, the company said in an announcement.

Peru's labour inspection authority, Sunafil, has opened its own investigation and dispatched inspectors to the site to determine the circumstances surrounding the accident. The agency has the authority to fine employers and order corrective measures if its findings point to safety violations.

MMG expects operations to restart progressively on Friday and has not updated its 2026 copper production guidance, a timetable that suggests the interruption could be relatively brief.

Las Bambas is one of Peru's largest copper mines and the cornerstone of MMG's copper output. It produced 410,829 tonnes of copper in 2025, 28% more than a year earlier, according to data from the country's Ministry of Energy and Mines, and contributes roughly 2% of global mined supply.

Supply pressure

The shutdown comes as other disruptions across South America add to concerns about copper availability. Lundin Mining (TSX: LUN) this week lowered its annual copper production guidance in Chile by 10,000 tonnes because of weather-related interruptions.

The pressure on mine supply matters because copper demand is being underpinned by electrification, with power grids, electric vehicles and renewable energy installations among the metal's fastest-growing uses.

Las Bambas has itself endured repeated disruptions since ramping up in 2015-16, largely due to protests and road blockades involving communities along the roughly 450-km route used to transport concentrate to the Port of Matarani.

Operations were disrupted for more than 100 days in 2019 as communities along the transport corridor sought action from MMG and the Peruvian government over truck emissions and the loss of farmland.

The mine shut completely for more than a month in 2022 after two communities that had previously sold land for the project re-entered the properties. One was later evicted, while Huancuire remained on the property, according to MMG.

Market impact

Because the latest suspension stems from a workplace accident rather than the social conflicts behind many previous stoppages, the disruption carries a different risk profile.

Its significance extends beyond the mine itself. Peru is the world's third-largest copper producer, behind Chile and the Democratic Republic of Congo, and copper is the country's top export, making mining a central pillar of the economy. Any extension of the shutdown could therefore compound supply pressure from other interruptions across the region.

The near-term markers are whether Friday's progressive restart proceeds as planned, what Sunafil's investigation concludes, and whether MMG revisits its 2026 guidance in the weeks ahead.