At least one person has died and 48 others injured following an explosion on Wednesday evening at Bree Street in the Johannesburg CBD.
Some 12 people still remain hospitalised.
Briefing the media on Thursday morning, Gauteng Premier Panyaza Lesufi said although there is a suspicion that the explosion was caused by gas, all relevant stakeholders who provide services in the area have been brought in to determine the cause.
"We have now formally brought all institutions that deal with gas. We now have EGoli Gas; we have brought Sasol and we are bringing anyone that has either underground pipes or caballing. Telkom, water and any institution that will assist us just to determine the cause of the impact and also give us the necessary advice.
"City Power...have since taken a decision to switch off the Bree Street substation so that the team can go in there and identify the cause and also assist us to identify areas that need our immediate intervention," he said.
Lesufi added that government agencies, including law enforcement, have moved quickly to secure the scene and keep residents safe.
"There are 10 teams representing both the SAPS [South African Police Service], JMPD [Johannesburg Metro Police Department] and POPs [Public Order Policing] and more members are being mobilised so that we can protect the scene and ensure that everything is fine.
"The Department of Human Settlements was assigned the big task of identifying the homeless and also those that have been asked to leave the area. We identified 3 Kotze Street...to be the area where we'll house everyone that needed housing.
"The provincial government and local government have started to set up a disaster process of identifying how quick can we rehabilitate the affected areas, especially those that will have a severe impact on the economic activity of the city," he said.
Investigating cause
Egoli Gas has denied culpability in the explosion, however Lesufi said "it is common knowledge that there is a high smell of gas in the entire area".
"Egoli Gas remains the centre of our focus because all of us agree that the cause of this explosion or impact is gas. So that we can isolate all institutions that have the legal mandate to deal with gas. We now know that Egoli has a blueline...that cuts across Eloff and Lillian Ngoyi [Bree] Street but we are told it's a low pressure facility.
"We have asked them to identify all their pipes...and they've given us this information and then we'll handover to those that are experts and they'll advise us on how to take this process forward," he said.
Traffic diversion
Lesufi said because Bree Street is one of the busiest in the city, diverting and directing traffic away from the scene has become "a headache".
Sign up for free AllAfrica Newsletters
Get the latest in African news delivered straight to your inbox
"The teams are trying extremely hard because we have closed major roads. Bree Street is one of the busiest roads in the CBD...there are lots of taxi ranks, there are lots of drop offs and there are lots of people that indicated their frustrations about the signage and the movement of areas where taxis are now stationed.
"But we are assured...that as soon as we get the cause of the explosion, they will move with speed to release some of the roads. But because we have to be cautious, majority of the roads remain closed.
"They will keep the area sterile until it is rehabilitated. Road closures and diversions will remain in place until further notice," he said.
Meanwhile, government has urged citizens to exercise caution when near the area.
"Government notes with sadness the explosion in the Johannesburg CBD and sympathises with everyone who was affected by the explosion.
"While the cause of the explosion is being investigated, we urge members of the public to use alternative routes, allowing space for the relevant authorities to complete their work on the scene," government said in a tweet this morning.
