The City of Jo’burg has warned that due to a network breach several of its online systems, including its website, e-services and billing system have been shut down for 24-hours.

In a Tweet, the City of Jo’burg says security experts are investigating the incident, which is expected to last 24 hours.

It has requested that any queries be directed to the city’s call centre or that residents keep an eye on their Twitter updates.

Meanwhile, it has been reported that the hack occurred at the same time on Thursday that several banks also reported internet problems, believed to be related to cyber-attacks.

According to Business Live, the group is called the Shadow Kill Hackers.

They have reportedly demanded the payment of four bitcoins by October 28 and have threatened to upload all the data onto the internet if the banks fail to comply.