Members of the Economic Freedom Fighters (EFF), a South African revolutionary socialist political party, targeted six H&M stores in the Gauteng province.
Innocent shoppers were forced to flee as activists swept through the stores, which included Africa’s flagship H&M stores in the upmarket suburb of Sandton, Johannesburg.
Pictures and videos on social media show dozens of chanting protestors, wearing the red uniforms of the ultra-left party, and ransacking the stores.
Swedish fashion group H&M apologised for the advert earlier this week following criticism from across the world, including Manchester United star Romelu Lukaku and basketball player LeBron James.
But Mbuyiseni Ndlozi, spokesman for the ultra-left EFF, said that was too little, too late.
He posted images of the carnage on Twitter along with the caption: “The time of apologies for racism are over; there must be consequences to anti-black racism, period!”
H&M South Africa did not respond to a request for comment, but its local website carried an apology for the advertisement.
“Our position is simple, we have got this wrong and we are deeply sorry,” the apology read.
Police said they were monitoring the protests, but that they had made no arrests so far.
In one instance officers were forced to use rubber bullet to break up the protests.
The protests come despite the mother of the model, Terry Mango, telling critics to “get over it”.
In a series of scathing Facebook posts, she wrote: “Am the mum and this is one of hundreds of outfits my son has modelled… stop crying wolf all the time, unnecessary issue here… get over it.
“I really don’t understand but not coz am choosing not to bur because it’s not my way of thing sorry.”
She also revealed she has been to all her son’s photoshoots and “this was not an exception”.
The image advertising the £7.99 jumper was removed from H&M’s US and UK websites shortly after the outrage broke and the retailer quickly issued a statement apologising to “anyone it may have offended”.
But many have already pledged to boycott the store, as The Weekend – a Canadian R’n’B star who produced menswear collections with the chain – said he was cutting ties with the company.
While music mogul P Diddy tweeted an altered version of the image, saying: “Put some respect on it! when you look at us make sure you see royalty and super-natural God sent glory.
“Anything else is disrespectful.”