The SA Post Office (Sapo) temporarily suspended operations at the Witspos mail sorting centre in Johannesburg after 18 employees fell ill after coming into contact with a white powdery substance that leaked from a parcel.

The Post Office said on Friday the suspension of operations was a precautionary measure  after staff became ill and were taken to hospital at about 7pm on Thursday.

All of them have since been discharged from hospital.

The parcel, originating from outside SA, and the leak were reported in one section of the mail processing centre, the Post Office said.

“The City of Johannesburg’s emergency management services and the police have been on site to assist with the incident since last night [Thursday].

“Bio-management and environmental teams are currently rehabilitating the working area and it is anticipated that operations will resume in the next 24 hours.

“The Sapo employee wellness management team together with management have made contact with the families of the affected employees and will also be debriefing the Witspos mail centre employees,” it added.

Customers were urged to “bear with us” as deliveries would be delayed by about 24 hours.

“Customers are cautioned that it is illegal to post any illegal, hazardous or poisonous substance,” said the Post Office.