Four workers have been killed following an incident at Canadian firm First Majestic Silver’s La Encantada Silver mine in the state of Coahuila, Mexico.

The company stated the cause of the deaths as gas intoxication.

The incident is said to have occurred during construction of the 790 ramp at the mine when gas accumulated in the area.

Media sources attributed the cause of the accident to an explosion, which was denied by the company.

In a statement, the company said: “It is believed the operator of a scoop tram lost consciousness while mucking the area. Three additional miners later arrived to the scene to provide assistance to the ill miner. The four men were carrying all required personal protection equipment, including safety belt breathing apparatuses, but sadly did not use the equipment.

“The emergency response crew was dispatched and successfully extracted the four miners before transporting them to the local hospital where they were later pronounced deceased.”

“It is believed the operator of a scoop tram lost consciousness while mucking the area.”

Currently, investigation is being carried out by the company and Mexican authorities to understand the facts of the case.

The company stopped mining operations at the mine in response to the accident.

Operations have since been resumed at the mine excluding the 790 area, which is expected to remain shut until the investigation is completed.

The mineralogy of the deposits at the mine is said to comprise iron oxides, carbonates and lead sulphates with high concentrations of silver values.