DURBAN, South Africa: South Africa's ruling African National Congress party on Wednesday condemned a wave of attacks against immigrant shopkeepers that has left at least six people dead and exposed sharp social tensions in the country.

The spate of attacks has targeted shops and homes owned by Somalis, Ethiopians, Malawians and other immigrants, despite heavy police patrols in the southern city of Durban and surrounding townships.

"Over the last couple of weeks our nation has been engulfed in a shameful wave of attacks by some amongst us against our country's immigrant population," the ANC, which has ruled South Africa since the end of apartheid in 1994, said in a statement.

"(These are) criminal acts against vulnerable and defenceless people who have sought refuge, solace and economic prosperity in our country.

"The very real challenges faced by the South African people ... cannot be blamed on people of foreign nationality."

The ANC statement came after accusations that President Jacob Zuma has failed to take a public stance against the xenophobic violence.

Durban's impoverished townships have been at the heart of the recent clashes between locals and immigrants, following a similar spate of attacks on foreign-owned shops in Soweto, near Johannesburg, earlier this year.

Over 1,000 foreigners in Durban have fled their homes and are now living in makeshift camps under police guard.

In one camp, Tarcisse Balole, 34, from Congo, was nursing 36 stitches in his head after being attacked by stick-wielding assailants in his spice shop on Friday.

"They said they would come and kill me. They took everything," he told AFP.

On Wednesday, many shops in the centre of Johannesburg were shut as owners feared that violence could erupt after threats spread via social networks and phone text messages.

"I've (been) 15 years here," Milion Kassa, a 34-year-old Ethiopian shopkeeper, told AFP.

"What did we do wrong except work hard to improve our lives? And are the police saving us? No."

Violence against immigrants in South Africa is common, with unemployed locals accusing foreigners of taking their jobs.

In 2008, 62 people were killed in similar violence in Johannesburg townships.

Neighbouring Mozambique is planning to help some of its citizens flee from Durban, the largest city in KwaZulu-Natal province, after Malawi announced its own repatriation plan on Monday.

"We have an experience which worked well in 2008, and it's ready to work again," Mozambican Foreign Minister Oldemiro Baloi told a press conference on Tuesday night.

King Goodwill Zwelithini, traditional leader of the biggest ethnic group in KwaZulu-Natal, has been blamed for fanning the attacks after a speech two weeks ago in which he told immigrants to go home.

On Wednesday, his representative condemned the attacks and denied the king had any responsibility for fuelling anti-immigrant sentiment.

"The king is saddened by what is happening. He never thought something of this nature could happen," Prince Thulani Zulu, speaking in Durban on behalf of the king, told AFP.

"The king condemns this, this is criminal."

Last month, the king gave a speech in which he was reported to have demanded that immigrants "pack their bags and leave".

Since then, six people have been killed in clashes between locals and foreigners in and around Durban, and 74 people have been arrested.

Police said Wednesday that the latest death was a 14-year-old boy killed in KwaMashu, a township north of Durban.

"We are trying to educate our people about the impact of what they're doing," said Mkululi White, of the Protection of Foreign Business and Citizens action group.

"Many foreigners have registered businesses, they're paying taxes, they are growing our economy."

Anti-xenophobic campaigners planned a march in Durban on Thursday to pressurise authorities to do more to protect immigrants.