South Africa mustered its army reserves on Thursday in a bid to quell looting that has ravaged supplies of food and other essentials and dealt a crippling blow to its economy.

"All reserve members are to report for duty at first light tomorrow morning 15 July 2021 at their respective units," army chief Lieutenant-General Lawrence Mbatha said in orders issued overnight as the unrest entered its sixth day.

Soldiers should "report ready with their necessary equipment," the defence ministry said in a statement.

On Wednesday, the government said it would call out around 25,000 troops to tackle the emergency -- 10 times the number that it initially deployed.

A man fires a gun in the air to disperse suspected looters outside a mall in the Johannesburg suburb of VosloorusUnrest raged in South Africa on July 14, 2021, for the sixth day running, stoking fears of food and fuel shortages as disruption to farming
A man fires a gun in the air to disperse suspected looters outside a mall in the Johannesburg suburb of VosloorusUnrest raged in South Africa on July 14, 2021, for the sixth day running, stoking fears of food and fuel shortages as disruption to farming, manufacturing and oil refining began to bite. AFP / GUILLEM SARTORIO

Stores and warehouses have been ransacked and torched around the economic capital of Johannesburg and in the southeastern state of KwaZulu-Natal.

The disruption has severed supply chains and choked transport links, savaging deliveries of food, fuel, medicine and other essentials.

According to official figures, 72 people have died and more than 1,200 people have been arrested, while South Africa's consumer goods regulatory body estimates that more than 800 shops have been plundered.

The unrest began a day after former president Jacob Zuma -- viewed as a champion of the poor by leftwing radicals -- began a 15-month jail term on July 8 for refusing to testify to a commission probing corruption under his tenure.

The government says it will deploy 25,000 troops to deal with the crisis -- 10 times more than it announced on Monday
The government says it will deploy 25,000 troops to deal with the crisis -- 10 times more than it announced on Monday AFP / Phill Magakoe

Protests quickly turned into looting as crowds pillaged shopping malls, hauling away goods as police stood by, seemingly powerless to act.

As the crisis escalated, the armed forces on Monday said they were sending 2,500 troops to help restore order.

The figure was criticised by many as paltry, given that 70,000 soldiers were deployed last year to enforce a strict coronavirus lockdown.

On Wednesday, Defence Minister Nosiviwe Mapisa-Nqakula told parliament she had submitted a request for "plus or minus" 25,000 troops.

The request came after President Cyril Ramaphosa told leaders of political parties that parts of the country "may soon be running short of basic provisions" following disruption to supply chains.

TV footage of the casual looting has deeply shocked many South Africans. Business confidence has been savaged at a time when the economy is already mired in unemployment, especially among young people.

Locals have started forming vigilante groups to protect infrastructure in their neighbourhoods.

A group of commuter minibus operators armed themselves with sticks and firearms on Wednesday and violently beat up suspected looters in the Johannesburg township of Vosloorus.