South African miner Gold Fields said on Friday workers at its Beatrix gold mine had stopped an illegal strike, but production had been affected.

They are up now. They have come to surface, said Andrew Davidson, spokesman for Goldfields.

At the day shift yesterday, 13,000 employees did not return to surface but instead decided to remain on five level of four shaft, which is 1,100 metres below surface ... and have an illegal strike, he said.

Davidson said production at shaft four of the mine had been affected by the strike because of a loss of Thursday night and Friday morning's shifts, but was unable to give exact figures.

This was an illegal action. It could have compromised the safety of many of our employees and the instigators of this incident could face disciplinary action, Davidson said.

(Reporting by Serena Chaudhry; editing by Christopher Johnson)

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