Eastgate Mall management alerted police after receiving a letter threatening that explosives would be placed in the centre, according to police spokeswoman Katlego Mogale.

“Members of the police responded with dogs and discovered an unattended suitcase” left near a jewellery store, Mogale told AFP.

“Upon inspection they found the suitcase was a bomb.”

Police detonated the device in a small, controlled explosion in the mall’s basement, after evacuating the centre.

Armed robbers periodically attack South African shopping centres, robbing jewellery stores of goods worth thousands of dollars.

The country registered a 61 percent rise in the year ending March 31, 2011 in the use of small bombs to break open automatic teller machines — a total of 399 incidents, according to official information.