President Thabo Mbeki gave the go-ahead Wednesday for troops to step in and quell a surge of anti-immigrant violence that has left 42 dead and driven thousands from their homes.
It would be the first time troops have been sent into Johannesburg's townships since the end of apartheid in 1994.
Police spokesman Govindsamy Mariemuthoo said 42 people had died and 16,000 had been displaced following about 10 days of unrest, most of it flaring in squatter camps that are home to impoverished South Africans and immigrants from neighboring countries.
About 400 arrests have been made, he said.
Mbeki approved a police request to have the South African National Defense Force help crack down on the ongoing attacks on foreign nationals in and around Johannesburg, a statement from his office said.
Mariemuthoo said details of how troops would be deployed still were being finalized.
Main targets of attack
Zimbabweans, Malawians, Mozambicans and others from neighboring countries have been the main targets of the attacks. They came to South Africa, the region's economic hub, looking for work and ended up sharing squatter camps with poor — and increasingly frustrated — South Africans.
Although South Africa is more prosperous than its neighbors, it suffers high unemployment and widespread housing problems, especially among the black majority.
Also Wednesday, there were reports of violence spreading to the port city of Durban, where police said a mob armed with sticks and bottles descended overnight on a tavern believed to be owned by a foreigner.
No one was injured in the attack Tuesday night, police spokeswoman Phindile Radebe said. She said the area was under control Wednesday and the case was being investigated.
It nonetheless raised concerns that the xenophobic violence in and around the commercial capital of Johannesburg in recent weeks could spread elsewhere in South Africa. Johannesburg is about 350 miles northwest of Durban.
Mariemuthoo, the Johannesburg police spokesman, said Wednesday that the situation had calmed but there were still reports of scattered violence coming in. The victims included a Malawian man who said he was beaten up when he tried to return to his shack to gather his belongings in a squatter settlement east of Johannesburg.
South Africa already has a reputation as a crime center, and the international attention the xenophobic violence has drawn could further erode investor confidence. It also comes as South Africa seeks to improve its image ahead of hosting the 2010 soccer World Cup.
Tourism Minister Marthinus van Schalkwyk, speaking to reporters in Cape Town earlier this week, was worried about the impact of the anti-foreigner violence on how tourists see South Africa. He said visitors from elsewhere in Africa made up the fastest-growing sector of his country's tourist economy.
"Africans increasingly travel to South Africa as a holiday destination," van Schalkwyk said. "These attacks have the potential to impact negatively on these markets."