Johannesburg, Feb 2 (IANS): More than 900 miners have been rescued after being trapped in a South African mine following a power failure, authorities said on Friday.

A violent storm had knocked out the electricity supply on Wednesday night, trapping the miners, the BBC reported.

The operation to rescue the trapped miners at the Beatrix mine in the Northern Free State got a boost on Friday morning when power was restored to a lift, said James Wellsted, spokesman of Sibanye-Stillwater which operates the mine.

"All the trapped miners were brought to the surface," Wellsted said, adding "there were cases of dehydration and high blood pressure but nothing serious".

Angry family members had gathered near the mine waiting to hear news of their relatives, who had spent more than a full day underground, the state broadcaster SABC reported.

"It was stressful, there was not enough ventilation," said mineworker Mike Khonto. "Thankfully our management managed to send us food and water."

Wellsted said there was "no indication so far that anyone has been in distress" but it had been a "traumatic experience".

Trade union officials had previously said they feared that the lives of the miners were at risk. More than 80 fatalities were recorded in South African mines in 2017.