South African police on Thursday arrested 20 people suspected of being among the instigators of riots that left hundreds of people dead last year in the worst unrest since the end of apartheid.

Authorities said joint police teams were mobilised to execute simultaneous arrests in various provinces.

The arrests came as detectives "made significant inroads" in probing incitement of public violence through social media and other platforms during a wave of unrest in July 2021, police said in a statement.

Parts of South Africa were plunged into chaos and more than 350 people were killed during almost ten days of rioting that followed the incarceration of former president Jacob Zuma last July.

An inquiry blamed glaring failures by police and intelligence agencies for the unrest that cost the economy some R50 billion ($3.3-billion).

Police said the 20 arrested suspects were expected to appear before a Durban court on Friday on charges ranging from conspiracy to commit public violence to incitement to commit arson.

The unrest broke out after Zuma was jailed for contempt over his refusal to testify before a commission probing state corruption during his presidency.

The rioting and looting started in his home region, KwaZulu-Natal, before spreading to Johannesburg.

Mobs overran dozens of shopping malls and warehouses, carting away flat-screen televisions, refrigerators, leather couches, and cartons of fresh meat.

The inquiry report published earlier this year said that while the riots were largely organised by protesters on social media, the masterminds had remained "largely faceless".

Last month, South Africa's Defence Minister said that one year after the violence, only 50 people had been convicted, while thousands of others were still awaiting trial.

Earlier on Thursday, the National Prosecuting Authority (NPA) said a Durban court had sentenced two more men to five years each on charges of public violence.

The perceived lack of progress in bringing the perpetrators to justice has been a cause of frustration for relatives of the victims and many others across the country which has one of the highest murder rates in the world.

Jacaranda News