By Hassan Isilow

JOHANNESBURG

A fire that broke out at Palabora copper mine in South Africa’s northern province of Limpopo on Sunday killed at least six miners, the company confirmed on Monday.

"Palabora Copper is saddened by the incident‚ loss of lives and continues to grieve with the families,’’ the company said.

Trade unions are calling for an immediate investigation into mining safety standards in South Africa, one of the world's largest producers of precious metals.

Dozens of workers have died or been trapped underground since the beginning of this year.