YUNNAN Chihong Zinc & Germanium, a unit of metals group Chinalco, said late Tuesday that one of its zinc subsidiaries had suspended production after three workers were killed in a gas leak.

Four employees of the subsidiary, Hulun Buir Chihong in Inner Mongolia, inhaled a toxic gas preliminary findings indicate was carbon monoxide during an inspection of equipment Monday evening, Yunnan Chihong said in a filing to the Shanghai Stock Exchange.

Three died at the scene and a fourth is being treated in hospital but is not in a life-threatening condition, it said.

Hulun Buir Chihong planned to produce 131,600 tons of zinc ingots in 2021 and churned out 60,700 tons in the first half, Yunnan Chihong said.

Production and operation at the subsidiary had been suspended on the orders of the local emergency management bureau, the company said.

The cause of the accident, duration of production halt and impact on the company are pending further investigation, according to the filing.

Yunnan Chihong said it would actively cooperate with the investigation into the incident and strengthen efforts to deal with potential safety hazards.

Zinc prices on the Shanghai Futures Exchange closed at 22,675 yuan (US$3,497.77) per ton Tuesday.

(SD-Agencies)