Johannesburg - Roofs were damaged in Protea Glen, Soweto, on Monday afternoon during a strong storm, Gauteng police said.
"There have been no reports of injuries so far," Warrant Officer Kay Makhubela said.
"It's just the roofs of houses were damaged."
He estimated that "more than 20" houses were damaged in the storm.
Weather SA forecaster Vanetia Phakula said she could not confirm media reports that Protea Glen experienced a tornado.
"From what we saw on radar it didn't look like a tornado... all I could see was the storm was moving very fast.
"I won't rule out the possibility (that it) was a tornado, but we would need to send someone out there to look at the damage."
This was because a tornado made a distinctive circular pattern of damage where it passed, she said.
Johannesburg Emergency Management Services spokeswoman Nana
Radebe said that it received reports of damage from the storm.
"We only just received a call from affected people. We have an officer en route but we don't have details yet."
Sapa