The South African military said on Monday it was deploying soldiers in two provinces, including its economic hub of Johannesburg, to help police cope with looting and arson attacks on businesses.
Soldiers could already be seen patrolling the streets of Pietermaritzburg at midday, but the army stated "deployment will begin as soon as all the processes" are in place to prepare.
"The South African National Defence Force has commenced with pre-deployment processes and procedures in line with a request for assistance received... to assist law enforcement agencies deployed in Gauteng and KwaZulu-Natal provinces respectively to quell the unrest that has gripped both Provinces in the last few days," it said in a statement.
The duration of the deployment and the number of soldiers mobilized will be determined "according to the assessment of the situation on the ground by the police", the military added.
The role of the military will be "to provide security and a safe working environment for law enforcement agencies" to do their job in better conditions while the police, widely deployed at most of the sites of violence, have often been overwhelmed in recent days.
Looting and fires spread across the country on Monday, on the fourth day of violence initially triggered by the imprisonment of former president Jacob Zuma, and later fueled by economic desperation compounded by restrictions imposed since late June in the face of a third deadly wave of Covid-19.
Zuma is serving time for defying a court order to testify before a state-backed inquiry probing allegations of corruption during his term as president from 2009 to 2018.
Despite his reputation for graft and scandal, the 79-year-old former anti-apartheid fighter remains popular among many poor South Africans.
The epicentre of the unrest is Zuma's home region, the southeastern province of KwaZulu-Natal.
Shortly before the military's announcement, troops were seen on the streets of its capital Pietermaritzburg and smoke billowed from the roof of a large shopping mall.
A retail shop in Durban was looted Monday morning while in Eshowe, a town near Zuma's Nkandla home, police fired rubber bullets to disperse crowds after a supermarket was ransacked.
In Johannesburg, in Gauteng province, an AFP photographer saw a corpse at one site. The cause of the death was not immediately known. Sections of a major highway were closed.
Police said more than 200 people had been arrested, and six were killed.
Some of the protests appear to have been triggered by Zuma's detention, but they are also associated with grinding unemployment and hardship inflicted by a toughening of anti-Covid measures.
President Cyril Ramaphosa on Sunday called on dissenters to protest peacefully.
"While there are those who may be hurt and angry at this moment, there can never be any justification for such violent, destructive and disruptive actions," he said.
Once dubbed the "Teflon president," Zuma started serving the jail term after handing himself in to authorities as a deadline for surrender loomed.
On Friday he lost a petition at the Pietermaritzburg High Court to have his case thrown out.
The court said it was not empowered to interfere with rulings set down by the Constitutional Court and that Zuma's claims about his health were not "supported by any evidence."
The anti-graft panel is probing the massive siphoning off of state assets that occurred during Zuma's 2009-2018 presidency.
He testified just once, in July 2019, but then swiftly withdrew his cooperation, saying he was offended at being treated as an "accused" and not as a witness.
Under the terms of his sentence, Zuma could be back home before Christmas as he would be eligible for parole in less than four months.
He separately faces 16 charges of fraud, graft and racketeering in an arms procurement scandal dating to 1999, when he was vice president.