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.

It will be a "mammoth task" to identify the bodies brought up from a disused mineshaft in South Africa this week, a police spokesperson says.

Illegal mining is common in parts of gold-rich South Africa. Typically, undocumented miners known as zama zamas - from an isiZulu expression for "taking a chance" - move into mines abandoned by commercial miners and seek to extract whatever is left. Some are under the control of violent criminal gangs.

Police say the death toll in a monthslong standoff between authorities and miners trapped while working illegally underground at an abandoned gold mine in South Africa has risen to at least 87.

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.

South African authorities have come under intense scrutiny for their response after civic groups said hundreds of miners have been trapped deep in an abandoned gold mine for months.