South Africa's top court began hearing a challenge by former President Jacob Zuma against a 15-month prison sentence on Monday, as angry supporters looted shops and set fire to buildings in protests.
Zuma was sentenced for defying a constitutional court order to give evidence at an inquiry investigating high-level corruption during his nine years in office until 2018.
The decision to jail him resulted from legal proceedings seen as a test of post-apartheid South Africa's ability to enforce the rule of law, including against powerful politicians.
In the virtual hearing, Zuma's counsel asked the court to rescind his jail term, relying on a rule that judgments can be reconsidered if made in the absence of the affected person or containing a patent error.
Legal experts say Zuma's chances of success are slim.
The looting followed a weekend of unrest by protesters, mainly been concentrated in Zuma's home province of KwaZulu-Natal (KZN), with some spilling into the main commercial city of Johannesburg.
Television channels showed footage on Monday of a blaze at a mall in Pietermaritzburg, in KZN. The channel said the highway leading to the city had been closed to prevent further violence.
A police spokesperson did not immediately respond to a request for comment.
Zuma's core supporters, echoing his position, say he is the victim of a political witch hunt orchestrated by allies of his successor, President Cyril Ramaphosa.
Ramaphosa said on Sunday there was no justification for violence and that it was damaging efforts to rebuild the economy, damaged by the COVID-19 pandemic.
Zuma's jailing marks a significant fall for an important figure in the liberation-movement-turned ruling party, the African National Congress (ANC). He was once jailed by South Africa's white minority rulers for his efforts to make all citizens equal before the law.
The corruption inquiry that Zuma has refused to cooperate with is examining allegations that he allowed three Indian-born businessmen, Atul, Ajay and Rajesh Gupta, to plunder state resources and peddle influence over government policy. He and the Gupta brothers, who fled after his ouster and are believed to be living in Dubai, deny wrongdoing.
Zuma also faces a corruption case relating to a $2 billion arms deal in 1999 when he was deputy president. He denies the charges in that case.