Four adult males sustained critical injuries including extensive burn wounds, in what is believed to be an aerosol container explosion, early today in a recycling factory in Germiston South.

The patients were treated on scene by Advanced life support paramedics from Netcare 911 and another service.

Two of the injured were airlifted by Netcare’s specialised helicopter ambulance, and two other seriously injured patients were transported by road ambulance to hospital for further treatment.

The incident was well controlled by the in house fire and safety crews.

Circumstances leading up to the explosion will be investigated by the SAPS who were on scene.