JOHANNESBURG - An earthquake on Sunday struck near Johannesburg, shaking buildings across Gauteng.
The tremor struck at 2.38am around 10 kilometres below the surface, the USGS said.
Residents across the province felt the tremor and some posted pictures on social media showing minor structural damage of walls.
Emergency services reported neither casualties nor injuries but said its disaster management teams would remain on standby.
Johannesburg emergency services spokeswoman Xolile Khumalo warned residents to "be on alert in case after tremors occur, (as) these tend to be more dangerous than the initial earthquake".
READ: Quake shakes Gauteng
The epicentre of what the provincial weather services described as a "relatively long tremor" was at Boksburg.
In August 2014, a 5.3 magnitude earthquake hit a gold mining town near Johannesburg.
The last major quake to hit South Africa was a 6.3-magnitude tremor that struck the Western Cape province in 1969.