By Rhiannon Hoyle

SYDNEY--Rio Tinto PLC on Wednesday said one of four furnaces at the Richards Bay Minerals mineral-sands business in South Africa will be shut off, as stockpiles of feedstock are depleted after mining was stopped amid escalating security issues.

Mining operations at Richards Bay Minerals, in which Rio Tinto has a 74% stake, were halted last month because of concerns about safety that followed the fatal shooting of a senior manager a month earlier. The world's second-biggest miner by market value declared force majeure on customer contracts.

"RBM will regularly reassess the situation to make further decisions on any potential restart or the shutting of the other furnaces, depending on when the safety and security position improves," Rio Tinto said Wednesday.

On May 24, Nico Swart, a general manager for mining operational services at Richards Bay Minerals, was fatally shot on his way to work, an earlier statement from the Rio Tinto subsidiary said. The operations subsequently faced problems with arson attacks and theft.

Write to Rhiannon Hoyle at rhiannon.hoyle@wsj.com

(END) Dow Jones Newswires

07-21-21 0246ET