Diliza Mthembu told the commission's special hearing on prisons in Johannesburg that he was tortured and beaten during his four and a half years' imprisonment, often for no reason.
"Prisons in Africa are very horrible. The conditions are bad," he said. He developed asthma and high blood pressure as a result of his imprisonment in various prisons in Angola.
He said he was an ANC chief-of-staff and the commander of a training camp called Caxito in Angola, as well as the ANC's representative in Benguela province in the 1970s.
His father, Abel Patrick Mthembu, a founding MK member and deputy leader of the ANC in then Transvaal, was killed by the ANC in 1978 when it was alleged he had betrayed the organisation. This was always used against him, he said.
When he was in Katenga, Angola in 1977 he was told his father had "sold the movement to the enemy".
In March 1978, a M Piliso had told him his father should be killed.
"He even tried to recruit me to go and to kill my father. Within a week I heard on (the ANC's Radio Freedom) that my father had been killed."
He said his own difficulties began with the ANC leadership when the two vehicles he had in his camp where ordered back to Luanda in 1982.
He refused as the two Land Crusiers were the only transport his camp had.
A few days later Angolan police and an ANC official arrived at the camp and he was jailed in a transit camp before being taken to Luanda, where he was locked in a cargo container for 28 days, without ventilation and often without food and water. He and a few other prsioners were let out once a day to go to the toilet.
He was then taken, via other camps, to Quatro.
Mthembu, now a staff sergeant in the SA National Defence Force, said he was accused of attempting to overthrow the ANC leadership.
During his time in Quatro he was beaten with sticks and tortured with electrodes attached to his body. He and other prisoners were also forced to pull a heavy water tanker.
"Twice I was forced at gunpoint to propose love to a tree and make love to it."
He was also forced to climb a tree full of wasps, lie naked on an ant-covered piece of ground, and chop down a tree in which bees had built a hive.
When a fellow prisoner went to the camp's hospital, he came back and described it as hell. The man was asked if he drank tea or coffee and when he replied coffee, he was then beaten with a "coffee stick".
Mthembu said the food was not healthy, and often prisoners were forced to go without meals. Some prisoners died because of malnutrition, he said.
"Torture was a daily thing. Torture used to take place even at the hospital. There was no escape even when you were sick."
He said conditions changed after the 1985 ANC conference, brought about by a mutiny at Quatro over poor conditions at the camp.
Inmates were given new uniforms, food and sleeping conditions were improved and windows were built into cell walls. But, the "beatings never stopped".
Mthembu was released from Quatro in 1988.
He travelled to Tanzania, where he was arrested and then released. He went to Malawi in 1990 where he was also arrested and detained for four months. He returned to South Africa in May 1990 and was arrested again and held at the Kimberley police station for three weeks.