Two South African National Defence Force (SANDF) soldiers have died after falling down an abandoned mine shaft while pursuing illegal miners west of Johannesburg.

The incident on Friday morning marks the first military fatalities since President Cyril Ramaphosa deployed troops in March to support police in tackling crime and illegal mining operations.

Police spokeswoman Athlenda Mathe said the soldiers were chasing suspected illegal miners, known locally as “zama zamas”, when they fell into an open vertical shaft at about 06:00.

The SANDF confirmed the deaths and said efforts were under way to formally identify the soldiers and notify their families.

Zama zamas, which means “those who try” in Zulu, are clandestine artisanal miners who operate in abandoned gold mines around Johannesburg. Many come from neighbouring countries, driven by poverty and unemployment.

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The illegal mining sector has become linked to organised crime, including assassinations, extortion and other criminal activities.

Last week, security forces arrested more than 200 people, mostly undocumented foreign nationals, during a raid on a gold mine shaft west of Johannesburg. Police said more than 100 were from Lesotho, with others from Mozambique, Zimbabwe and South Africa. Guns and ammunition were confiscated during the operation.

The arrests come as South Africa intensifies its crackdown on undocumented migrants. According to figures from African countries that have repatriated their nationals, more than 150 000 people have returned home in recent weeks.

The military deployment, codenamed Operation Prosper, involves more than 2 200 soldiers and is scheduled to last one year.

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