Twenty-eight female guards were unfairly dismissed by a security company because the client‚ Metrora.
The South African National Defence Union (Sandu) is demanding an inspection of weapons similar to the computerised gun that killed nine soldiers when it malfunctioned during a training exercise at Lohatla in October.
Sandu said yesterday it wanted the South African National Defence Force (SANDF) to "temporarily withdraw all such weaponry from active duty", including operations and exercises.
This, pending a complete and substantial safety check and safety certification by independent ballistic experts.
A preliminary police investigation has found no indications that negligence was to blame for the shooting, which also injured 14 soldiers.
Captain Cherelle Ehlers said on Monday that the police investigation was at an advanced stage.
A separate investigation by the SANDF has apparently been concluded, but will not be made public until the families of the dead soldiers are informed.
Sandu said the police ballistics report indicated that the weapon involved had mechanically malfunctioned.
"This finding vindicates Sandu in the concern it expressed publicly as to the maintenance and age of the specific weaponry in question," Sandu acting national secretary Pikkie Greeff said.
"There now exists reason to doubt the safety of all weaponry of similar age and function."
Sandu also demanded that, in the interest of transparency, the findings of the SANDF investigation be made public "without further delay".
They needed to be compared with the police findings and those of an investigation by the Labour Department.
"The findings of the SAPS already indicate by implication legal liability by the Department of Defence in this incident," said Greeff.
The Defence Department now had to do what was "morally and legally correct" in making proper offers of compensation to the injured victims and the families of the dead.
It also has to take "decisive and visible steps" to show soldiers the weapons were being independently inspected and certified or decommissioned to ensure their safety in an already hazardous occupational environment, he said. - Sapa