A weeklong uprising in Peru’s Moquegua region has placed strain on copper supplies worldwide.

The unrest began as a small protest over how little in the way of mining profits was being used to help residents of the region, but quickly swelled to 20,000 people blocking major highways and railways, including a border crossing into Chile. Protesters also blocked roads to a mine and smelter operated by Southern Copper, the country’s largest copper producer. The company warned that if access was not immediately restored, the Ilo smelter might have to be shut down due to supply shortages.

Union workers at the Cuajone mine in the region staged a two day strike in solidarity with the general unrest. Government and police offices were also burned.

When riot police attempted to clear the roads, protesters fought back, injuring 20 police and taking 60 hostage. The police were released two days later.

On June 19, the government and protest leaders reached a deal to end the blockades in exchange for public works in the region. A mostly unrelated strike at the nearby Cerro Verde mine (Peru’s largest copper mine) remains unresolved, however.

The troubles in Peru are only the most recent major supply disruptions to hit the copper industry in the last few years.