Security forces threw a cordon around the High Court in the southeastern city of Pietermaritzburg, capital of Zuma’s home region of KwaZulu-Natal, where loyalists have previously gathered in rowdy shows of support.
The measures were later eased to allow street access after the area was deserted.
Zuma, 79, faces 16 charges of fraud, graft and racketeering related to the 1999 purchase of fighter jets, patrol boats and equipment from five European arms firms when he was deputy president.
He is accused of taking bribes from one of the firms, French defence giant Thales, which has been charged with corruption and money laundering.
The trial started in May after numerous postponements and delays, as Zuma’s legal team battled to have the charges dropped.
An emotionless Zuma made a virtual appearance from prison in the nearby town of Estcourt, sitting on a black office chair in a white-walled room, clad in a black suit, white shirt and red tie.
He had proclaimed his innocence when he appeared in person for the opening in May. Thales has also pleaded not guilty.
On June 29, Zuma was separately found guilty of contempt of South Africa’s top court for snubbing graft investigators probing his time as president. He was jailed on July 8.
Seeking another delay
South Africa then plunged into chaos, with looting and rioting erupting in KwaZulu-Natal, before spreading to the economic hub of Johannesburg, claiming more than 200 lives.
The total bill could reach 50 billion rand ($3.4 billion), according to consultancy Intellidex.
The unrest, which fell back at the weekend, was widely seen as at least partially in response to Zuma’s imprisonment.
The trial is resuming virtually to avoid more “disruption”, the National Prosecuting Authority (NPA) told AFP, although other court cases are also being heard online due to the pandemic.
But Zuma’s legal team claims the online format is unconstitutional and has applied for the trial to be adjourned.