Four Coin Security employees, who were arrested this week in connection with the R50million heist at a company depot last Saturday, have been released.
Police revealed yesterday that the four men were released on Wednesday.
They were arrested after a gang of seven armed men stormed the company's depot in Mooderfontein.
The gang had been disguised as security guards.
Company managing director Hendrick Kekana this week said the four had been "immediately identified through sophisticated surveillance equipment".
He said the equipment identified the men, though they wore masks.
Asked why the men were released, provincial police spokesman Director Govindsamy Mariemuthoo said: "At the time of their arrest there was reasonable suspicion of their involvement."
The men were held in police custody for four days for questioning.
They were not charged.
Mariemuthoo said no more arrests had been made, but investigations were continuing.
Sowetan's efforts to get comment from Coin Security were unsuccessful.
A statement sent to Sowetan by the company on behalf of the managing director said: "Sorry - Hendrick Kekana would not like to comment."
Mariemuthoo said that though the four men had been released, they would still form part of their investigation.