A miner at Kansanshi in Solwezi has died from suspected gassing while four others are battling for three lives in hospital.
Company public relations manager Godfrey Msiska said the one of the other four was still critical.
According to a statement, Msiska said arrangements to evacuate the miner in a critical condition to Ndola were underway.
Msiska said the other miners were in stable condition. The mining firm regrets the death of one of its employees after he arrived at the hospital following the suspected gassing.