South Africa’s president has ordered thousands of military personnel to assist in a nationwide operation against illegal mining, an activity that is estimated to cost the country billions of dollars each year.

The president’s spokesman Vincent Magwenya announced on Thursday that 3,300 army personnel would partner with police in an intensified anti-criminality operation against illegal mining across all provinces.

The mission will run until April 2024 as part of President Cyril Ramaphosa’s Operation Prosper to instil law and order. Informal miners have been dubbed “zama zamas” the Zulu term for people who try their luck – as they risk their lives in disused mines and rudimentary tunnels, scraped into the earth without safety measures.

A gas explosion in May killed approximately 31 miners working illegally in the city of Welkom, trapping their bodies underground. Recovery efforts were stymied by high levels of methane in the mine – and the threat of further explosions.

In July, 17 people including three children were killed in Angelo Tivani, a settlement of about 200 people just outside Johannesburg. The activity also causes South Africa’s economy to lose out on tens of billions of rand in export earnings, taxes and royalties, the council estimates.