Families are demanding answers after eight people were killed in an explosion at Denel in Somerset West on Monday afternoon.
The explosion occurred at a factory with witnesses saying they heard a huge blast.
Acting president David Mabuza has called for an urgent investigation.
The State Security Minister Dipuo Letsatsi-Duba has addressed the media and families.
Speaking to Ray White on The Midday Report, Letsatsi-Duba says at this point they don't know exactly what happened.
The file where the accident happened is still closed and we are told it is dangerous for us to go there, it is only forensic people who are at the site.
— Dipuo Letsatsi-Duba, State Security Minister
She adds that company officials briefed them as to what they think might have transpired.
They said there was an explosion where they process the propeller manufacturing and they were not even sure of the number of people who died.
— Dipuo Letsatsi-Duba, State Security Minister
Listen below to the full interview: