A Johannesburg Metro Police Department officer walks between burnt cars at a car showroom in Johannesburg on Sunday. Several shops are damaged and cars burnt in Johannesburg, following a night of violence. Photo: VCG

Sporadic violence has erupted in South Africa, with dozens arrested after looting in the eastern KwaZulu-Natal province, where ex-president Jacob Zuma is in jail, and in the economic capital Johannesburg.

Police said in a statement Sunday they had arrested 37 people in KwaZulu-Natal and 25 in Johannesburg over the previous two days.

In KwaZulu-Natal, protests broke out a day after Zuma was imprisoned on Thursday.

The N3 highway linking coastal city Durban and Johannesburg was blocked for many hours, including a stretch south of Estcourt prison, where Zuma is being held.

Around 23 trucks were set alight at Mooi River around 150 kilometers northwest of Durban. Although some of the protests appear to have been triggered by Zuma's 15-month detention for contempt of court, they are tied in with a sense of economic desperation as the country faces tightened restrictions under a third wave of the COVID-19 pandemic.

"We don't know yet what the strike is all about... but from what people have been saying it's something related to our former president," Sphamandla Ndlazi told AFP in the Jeppe neighborhood of Johannesburg, with looted shops and burnt cars in the background.

President Cyril Ramaphosa reiterated calls for calm on Sunday in a speech focused on COVID-19 restrictions, urging people to express themselves "in peaceful protest" and avoid acts that endanger lives and damage the economy.

But looting was continuing into Sunday evening in the area around Durban.

"People have been intimidated and threatened, and some have even been hurt," Ramaphosa said, adding that "some people may have died."

AFP journalists saw the body of a man covered by a blanket in the gutter of a street in Jeppe.

Police spokesperson Brigadier Mathapelo Peters later confirmed the death to AFP, but the man's identity and the circumstances of his death were yet to be made public.

In KwaZulu-Natal, the police "had their hands full yesterday and throughout the night," spokesman Jay Naicker told AFP on Sunday.

"Criminals and opportunistic individuals" took advantage of the tense climate to "enrich themselves," he added. Several stores were looted, including some in the Durban suburb of Mariann Hill.

In Johannesburg, hundreds defied restrictions to demonstrate in two disenfranchised suburbs late Saturday, but their protests ended in violence, looting and 25 arrests, police said. 

In Jeppe, police dispersed a crowd of 300 who had set up barricades on a main road before looting businesses.

Similar scenes unfolded in Alexandra, one of the poorest townships that neighbors the well-off city of Sandton, where nearly 800 rioters clashed with the police overnight. 

One officer was shot and hospitalized and police said they "remain on high alert" on major roads and at hot spots in both KwaZulu-Natal and Gauteng, where Johannesburg is located.