In Bolivar state, NGO SOS Orinoco wrote on X that an operation was underway in "strategic areas" of Las Brisas and Las Cristinas, where there are "enormous mineral reserves" and "a history of international legal disputes."

Mining activity is concentrated in a vast area spanning 112,000 square kilometers (43,000 square miles) known as the Orinoco Mining Arc in the east, and there are also mines in southern Amazonas and Bolivar states.

Venezuela has the world's largest proven oil reserves, and it is also rich in gold, diamonds, bauxite and coltan, a mineral essential for technology and defense that is classified as critical by Western powers, as well as rare earths.

SOS Orinoco, which has been critical of Venezuela's government, said helicopters have been deployed and are engaged in clashes in another sector, Las Claritas.

In a post on X, human rights NGO Proveo called for the Venezuelan ombudsman to "intervene" and "oversee the operation."

Interim president Delcy Rodriguez, who rose to power after the US captured Nicolas Maduro in January, is pushing for a new law that would open up Venezuela's mining industry to foreign investors.

The primary mining regions, however, are under the control of armed groups who terrorize and extort the population.