The death toll from a mining tragedy last week in South Africa that involved an elevator has risen to 13 people after a worker died at a hospital, the mine operator said Monday.

Impala Platinum said that the worker died Sunday from injuries sustained when the elevator plummeted around 650 feet down the shaft of a platinum mine while carrying workers to the surface after their shift on Nov. 27. Eleven workers died that day, while the latest victim was the second mineworker to die at a hospital.

11 DEAD, SCORES INJURED AFTER SOUTH AFRICAN MINE ELEVATOR PLUMMETS 650 FEET

The mine operator said that 50 workers remained hospitalized, with eight of them in critical care.

Impala Platinum and the South African government announced an investigation into what mine officials called a highly unusual tragedy.

The industrial elevator was carrying 86 workers to the surface when it suddenly dropped back down into the shaft, which is about a ½-mile deep. The mine in the northern city of Rustenburg was the world's biggest platinum producer last year. South Africa is by far the world's biggest platinum-producing country.

Impala Platinum said it would hold a day of remembrance on Wednesday, when it would release the names of the workers who died.