DIEPSLOOT, South Africa (AFP) - South African police guarded foreign-owned shops in an impoverished Johannesburg township on Monday after a mob looted stores overnight amid simmering anger at immigrants.

Foreign shop owners packed their wares in trucks as armoured police vehicles patrolled the dusty Diepsloot township north of Johannesburg, where rubber bullet casings and burnt tyres littered the streets, an AFP reporter said.

On Sunday, police dispersed more than 100 people who went on a rampage after a Somali shop owner allegedly shot dead two people, according to police.

"Two people ... were shot dead by a shop owner who alleged that they were trying to rob him," Mr Lungelo Dlamini told AFP, adding that the victims were from Zimbabwe.

The crowd looted some shops in the area after the shooting, he added. "Police intervened and the crowd was dispersed," he said.

He denied that police fired rubber bullets to break up the mob.

Police kept a close eye as foreign business owners took away products ranging from baby nappies to televisions and cooking pots.

Amid widespread poverty and unemployment, frustration in South Africa's run-down neighbourhoods often boils over into anti-immigrant violence.

"I risk my life," said a Somali man named Hassan who was helping his brother move.

"There are a lot of problems. A lot of people robbed the shop," he added.

"I must remove all this stuff." Some locals were adamant the foreigners were unwelcome. "We don't like the Somalis. They must just go," one resident told AFP.

Last week, mobs looted foreign-owned stores in townships around Johannesburg.

Police arrested 93 people on Thursday and Friday for public violence and looting in Evaton, Sebokeng and Orange Farm in the south, local media reported.

The vandalism here started out as protests over poor service delivery.

The recent incidents have raised fears of a repeat of xenophobic attacks that killed some 62 people in 2008.

Rights group Amnesty International has decried ongoing violence against especially African immigrants in South Africa - often with the complicity of police.

Last year "numerous incidents of looting and destruction of shops and displacement of recognised refugees, asylum-seekers and migrants were documented," Amnesty said in an annual report released last Wednesday.

Almost 700 mainly Ethiopian nationals were displaced last year after their shops were looted in the central Free State province, according to the report.

Police also closed down "at least 600" foreign-owned small businesses in the northern Limpopo province during an unannounced and indiscriminate crackdown staged last year.

"Some asylum-seekers and refugees were subjected to xenophobic verbal abuse, detention and charged or fined for running their businesses," the report found.