South Africa's president is facing calls to order an inquiry into a police operation that was meant to combat illegal mining but ended up leaving 87 miners to die underground as authorities attempted to force them to surrender during a monthslong standoff.

The clampdown on illegal mining cut off food and water to hundreds of miners underground. At least 78 bodies were pulled from a mining shaft this week, and more are believed to remain underground.

The prospectors were trapped underground for months as police, on orders from South Africa’s government, attempted to starve them out.