A fire alarm at Brigitte Mabandla College in Pretoria prompted the precautionary evacuation of attendees, including members of the media, on Monday morning.
The alarm was activated shortly before proceedings of the Madlanga Commission were scheduled to begin at 9.30am.
No injuries have been reported.
City of Tshwane emergency services responded to the venue following the alarm, while an investigation is under way to establish what triggered it.
The commission is expected to hear testimony from alleged underworld figure Vusimuzi “Cat” Matlala on Monday.
Proceedings are expected to resume once authorities have cleared the venue and confirmed that it is safe.