Johannesburg - The Johannesburg City Council said it had detected a network breach which resulted in unauthorised access to its information systems.
In a statement posted on its Twitter account late on Thursday, the city said cyber security experts were investigating the incident and had taken immediate and appropriate action to reinforce security measures and mitigate any potential impact.
"As a result several customer facing systems - including the city's website, e-services, billing system ... have been shut down as a precautionary measure," it said.
The council said the investigation, set to take 24 hours, meant that customers would not be able to transact on e-services or log queries via the city's call centre or customer services centres. All emergency calls had been diverted to the provincial call centre.
The city pledged to update residents on a four hourly basis.