South African emergency workers rescued eight miners trapped a mile underground by a fire and rockfall in Harmony Gold's Doornkop mine, but nine others were unaccounted for.
Rescue teams battled through smoke and debris at a depth of 1700 metres to reach the eight on Wednesday (local time). The miners had managed to flee to a refuge bay equipped with a telephone and other survival items.
"Efforts continue to establish the whereabouts of a further nine employees who are currently unaccounted for," the company said in a statement.
Chief Executive Graham Briggs cancelled a presentation at a major industry conference in Cape Town to fly to Johannesburg to oversee the rescue effort at the mine, 30 km (20 miles) west of Johannesburg. Normal mining operations were suspended.
"There were 139 underground and 35 people in the affected area," Briggs told journalists at the mine. "All of the (rescued) miners walked quite comfortably when they came out. They are under observation for the next 24 hours."
The National Union of Mineworkers said the fire broke out on Tuesday evening after an earthquake damaged ventilation and water pipes as well as power cables.
"The damage to the electric cables triggered the fire underground, which is still burning," it said in a statement.
South Africa's gold mines are the deepest in the world and ranked as some of the most dangerous during the apartheid years. Since the end of white-minority rule in 1994, the government, unions and companies have worked hard to improve safety, but 112 people were still killed in 2012, the last year for which records are available.
Tumi Mokgele, a Doornkop miner who was on the ground level when the accident happened, said the incident highlighted the need to increase wages for workers and vindicated those who have gone on strike in the country's platinum belt.
"Then you say the 12,500 rand (wage hike) that we want is a lot. It's small," Mokgele told Reuters.
At least 82 men - thought to have been illegal miners - died after an underground fire at a Harmony mine in 2009. Most of the victims are believed to have died of suffocation.
All miners carry emergency oxygen packs and rescue bays are equipped with food, water and breathing equipment in the event of prolonged underground entrapment.