Three children died at a high school in Vanderbijlpark after a walkway collapsed on Friday morning.
Details are sketchy at the moment on what led to the accident.
On teacher told News24 that the walkway collapsed as children returned to class after attending assembly.
There are reports that several people are still trapped under the rubble.
"Multiple people have sustained injuries ranging from minor to moderate, at least five people are in a critical condition," Netcare's Shawn Herbst said in a statement.
Rescue teams are on the scene.
Gauteng MEC Panyaza Lesufi is on his way to Höerskool Driehoek following the tragedy.
This is a developing story.