Political detainees at the notorious John Vorster Square, now known as Johannesburg Central police station, complained that they were tortured daily, the inquest into the death of Neil Aggett has heard.
Their complaints included tales that they were assaulted, electrocuted or ordered to stand for long periods while holding their hands in the air.
This was the evidence of former security branch policeman Joe Nyampule, who testified at the inquest, held in the Gauteng High Court in Johannesburg, on Monday.
He said it was highly impossible that Aggett committed suicide.
"Holding cells were patrolled hourly 24 hours a day by uniform-wearing officers. Us, as security branch officers, we peeped through a hole in the door every 15 minutes [to see] if the person is still alive.
"If a person was asleep, he would be called to see if he would respond because we were told by the head of the unit, Arthur B Conrad, that detainees were suicidal," Nyampule said.
He added that after they were interrogated, detainees were asked if they had an issue to raise.
If they were assaulted, some detainees would say but others would just point out their injuries. These would then be noted.
"It was impossible that Aggett committed suicide because there were police officers there to see if detainees are alive. It was procedural that officers must write down their patrols in the occurrence book," Nyampule said.
No patrols or visits to Aggett's cell were recorded in the occurrence book for three hours from 22:20 on February 4, 1982.
"I am surprised that there were no patrols and visits to Aggett's cell. Three hours is a long time. Procedurally, it was expected to be done hourly. It was a must.
"According to me, there were supposed to be disciplinary hearings against those who didn't patrol his cell. I am shocked by claims that officers were overworked and failed to patrol Aggett's cell hourly as it was required," he said.
Nyampule also testified that he would take detainees to the infamous 10th floor where his white colleagues would interrogate them.
The inquiry continues.