The South African Post Office has suspended the postman who dumped mail at a taxi rank at Magagula Heights, Ekurhuleni, two weeks ago.
The postman, who name cannot be named because of the pending investigation, was a contract worker.
"The South African Post Office has a zero tolerance policy towards all forms of mail crime and takes disciplinary steps against all employees who fail to deliver mail," spokesman Malusi Fuphe said.
Sowetan published the story of the shocking discovery of large quantities of undelivered mail that was dumped at a nearby taxi rank.
The discovery, according to residents, confirmed their long-held fears that someone might be tampering with their mail.
"To make sure this problem does not occur again the supervisor in the area is now regularly doing spot checks and proper time boxes will be installed in the area as soon as possible," Fuphe said.
He said the dumped mail was delivered the following day.
But Fuphe said the area was so large that postmen could not be expected to carry heavy letter bags with them all the way.
So the Post Office would erect time boxes - lockable metal boxes - in which postmen can safely leave letters meant for one portion of their delivery area while they deliver the letters for another area.