A key railway access to Bolivia’s San Cristobal mine has been blocked by local residents since Monday forcing the mine to store mineral ore on the site.

The Bolivian Mining Ministry said it did not know what the protestors were arguing for, but said the rail line they have positioned themselves at links the mine with the main rail network.

An official associated with the San Cristobal mine said it had been stocking minerals since the blockage started, according to Reuters.

The mine official, however, did not say whether the mine was still able to export ore by road or if any stocks are held in Chilean ports.

San Cristobal mine exports all of its mineral production to foreign markets through Chile.

San Cristobal is one of the largest mines in landlocked Bolivia and produces about 1,300t of zinc-silver ore and 300t of lead-silver ore a day.