South African police on Monday arrested dozens of people following widespread looting and protests in the transport industry linked to a wave of anti-foreigner sentiment.
At least 70 people have been arrested since hundreds of people marched through Johannesburg's Central Business District (CBD) earlier on Monday, plundering shops and torching cars and buildings, the police said in a statement.
The unrest started on Sunday when an old building in the CBD caught fire and collapsed, killing at least three people.
It then spread to two eastern suburbs and to the capital Pretoria, where local media reported shops burning in the Marabastad - a central business area largely populated by economic migrants.
Police also said they were investigating a death in Hillbrow, a residential neighbourhood in central Johannesburg, where a "member of the public" was allegedly shot by a group.
"At this stage police are still interviewing several people to establish the motive," said a statement by the provincial commissioner.
Such violence breaks out sporadically in South Africa, where many nationals blame immigrants for high unemployment, particularly in manual labour.
South Africa is a major destination for economic migrants from the southern Africa region, with many moving from neighbouring Lesotho, Mozambique and Zimbabwe in search for work.
Police Minister Bheki Cele insisted recent violence was linked to "criminality" rather than "xenophobia".
"(Xenophobia) is used as an excuse," Cele told journalists after a tour of the CBD.
"For now there is nothing that has sparked any form of this conflict between the South Africans and foreign nationals."
'Enough is enough'
Nigerian Foreign Minister Geoffrey Onyeama reacted strongly to the scenes of violence.
"Received sickening and depressing news of continued burning and looting of Nigerian shops and premises in #SouthAfrica by mindless criminals with ineffective police protection," he said on Twitter.
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