Hackers demanding a ransom of four Bitcoins have brought Johannesburg to a standstill after crippling the city authority’s digital network.

Systems suffered a major security breached in the early hours of this morning, bringing the daily operations of an official body serving four-and-a-half million people to a shuddering halt.

A group calling itself the Shadow Kill Hackers now claims to have the private data of millions of South Africans, threatening to leak it all unless four Bitcoins – about R400,000 Rand – are deposited into a secret digital wallet by Monday.

In response, officials have taken down all its online facilities – from the official government website to e-payment systems.

Adding to the confusion, the city’s deputy director of communications – Nthatisi Modingoane – denied there had been any ransom demand, but said specialists were investigating.

“The City can confirm that we do not have any formal demand for a ransom,” he said.

“The hacking happened at the user level – not at the application level, as such. So, the application level – that’s where the critical data sits, and that part has not been affected as yet.

“When we noticed the user level being impacted we shut down the system as a precautionary measure to protect the integrity of our data to make sure the critical information of our customers is not compromised.

“We’re at the group IT building where we have set up a joint operations centre where people have been working through the night – they’re very exhausted.

“We’ve reconvened to try and bring the system up as quickly as possible.”

Behind with taxes

He urged people with an urgent need to make payments to use EasyPay in order to not fall behind with taxes and rates etc, adding he would personally keep Johannesburg’s residents updated on an hourly basis.

“We can’t give an exact time, but we can assure residents that part of the system will be up this weekend – starting this afternoon,” he said.

“At the moment we are not sure, and we don’t want to send panic to the public.

“There is also a team of very skilled and highly capable investigators who are also trying to make the preliminary investigations [into the group demanding the ransom].

“Once we get clarity of their details, we will be able to share with the people of Johannesburg in terms of what we have found and if there is any truth in this ransom demand.”

Mr Modingoane also explained that detectives were investigating alleged threats made to City staff on social media that are believed to be linked to the hackers and their crypto demands.

He added that officials were also working with South Africa’s banks in order to “strategise together to protect the data of the residents of Johannesburg”.

Earlier this year, City Power suffered a major security breach after hackers planted a virus which encrypted the databases of the utility forcing authorities to shut down digital services across Johannesburg.