Gold Fields Ltd said on Thursday it had shut one shaft at its key Kloof mine in South Africa to allow investigations to take place after two miners were killed following a tremor.

The employees were killed in a fall of ground at Kloof's No.4 Shaft while carrying out cleaning duties, some 3 km below surface. The tremor rated 1.2 magnitude on the Richter scale.

All production at the shaft has been stopped and an investigation by the Department of Minerals and Energy is being carried out, Gold Fields said.

It was not immediately clear how much output would be lost. (Reporting by James Macharia)

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