The threats were being sent on the Whatsapp platform on a day thousands of South Africans took to the streets in Durban protesting against a fresh wave of attacks against foreigners in the country.
Foreign shopkeepers were moving to safe areas despite assurances by the police that they will be safe.
Thousands of people have been displaced from their homes following xenophobic attacks in the coastal city of Durban and surrounding areas in Kwazulu-Natal province.
President Jacob Zuma has condemned the attacks on “our African brothers and sisters”.
Meanwhile, thousands of people marched through the streets of Durban Thursday calling for an end to the violence against foreigners.
Durban was the epicentre of the violent attacks that took place earlier this week.
The marchers, led by religious and political leaders, including the premier of the province, wanted to send a clear message against the xenophobic attacks.
Marchers carried various placards including one with a painting of birds’ drinking water symbolising their love for neighbours.
Other posters read: ‘Xenophobia is racism.’ Some of the marchers said they were embarrassed about the violence against innocent people.
Police warned that they would not tolerate any violence and maintained a heavy presence in the city centre.
Horrific pictures of women fleeing with their babies, men brandishing knives and police keeping locals and foreign national apart have dominated local television screens.
Reports say five have been killed and over 2 000 displaced by the violence.
The anti-foreigner sentiment has been blamed on South Africa’s rising unemployment estimated at over 25 percent and worsening poverty.
Locals accuse foreigners of taking their jobs and other opportunities.
Malawi has started evacuating its nationals and Zimbabwe on Thursday said it will assist those willing to return home to do so.
South Africa experienced the worst xenophobic violence in 2008 where over 60 people died.
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