Police fired rubber bullets at hundreds of shantytown residents Tuesday in a crackdown on attacks against foreigners that have killed at least 24 people.
The army could be called in to quell the violence, Jacob Zuma, the president of the ruling African National Congress, said in a radio interview.
Attacks on African migrants have continued for more than a week, with many poor South African township dwellers accusing the foreigners of stealing jobs and fueling a wave of violent crime.
Local media said two people were killed overnight in the Ramaphosa squatter settlement east of Johannesburg.
Police fired rubber bullets to disperse about 700 people who earlier forced foreigners from the area, a cameraman said. At least two people were injured.
Thousands of foreigners, mostly from Zimbabwe, Mozambique and Malawi, have fled into refugee shelters since the violence began May 11 in Alexandra township.
Several foreigners have been burned to death, women raped and scores of shops and homes looted. More than 200 people have been arrested.
Zuma told the BBC World Service that criminals were using the attacks as a cover.
The ruling party said it had sent officials into townships to urge an end to the attacks.
Police also increased their deployment to trouble spots.
"We are going hard on the situation," Safety and Security Minister Charles Nqakula said.