Twenty-eight female guards were unfairly dismissed by a security company because the client‚ Metrora.
The bulk of the estimated R14million stolen from the Absa cash depot in Witbank, Mpumalanga, has not been recovered.
The police confirmed that four people, including a security guard who worked at the bank, have been arrested. The security guard has already appeared in court.
The police refused to say how much was recovered but confirmed that "it was very little".
The money was stolen on Saturday afternoon after an unknown number of men held up three on-duty guards at Absa.
The four people were arrested by a crack team of investigators from the Mpumalanga organised crime unit under the leadership of Captain Welcome Gcabashe.
Three were nabbed in Soweto.
According to Captain Leonard Hlathi of the Mpumalanga organised crime unit far less than the stolen cash was recovered.
Meanwhile, the security guard, Emmanuel Ndlovu, 30, appeared briefly in the Witbank magistrate's court yesterday morning.
He was remanded in custody and his case was postponed to September 9 for further investigations.
He will appear with the rest of the detainees on that date.
Hlathi said the other three detainees had not yet appeared in court because investigations were still continuing.