South African President Cyril Ramaphosa is facing calls to order a national 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.

Rescue teams in South Africa have stepped up efforts to pull out survivors and the corpses of illegal miners trapped underground for about two months, following one of the most extraordinary tragedies to hit the industry.

The authorities had at one point limited the miners’ access to food, water and other supplies in a blockade that drew criticism from human rights groups.