Soldiers from the South African National Defense Force are expected to arrive in the township of Alexandra in Johannesburg by 6 p.m. Tuesday.
Al-Shabab didn't immediately take responsibility, but the attack bore some of the group's trademarks.
The Nigerian government will start evacuating citizens from Durban, Johannesburg and other hot spots in South Africa where xenophobic violence has spread.
The Ethiopian runner, who also finished first in 2013, was the favorite. Kenya's Carolina Rotich won this year's women's race.
"It's one more step towards connecting the whole world,” Facebook founder Mark Zuckerberg wrote in an online post.
Police urged spectators not to bring large bags or coolers, saying that such packages would be subject to search.
The casualties included two Kenyans and seven Somalis, a police official told Reuters.
Runners and their finishing times are easily searchable online.
Xenophobic violence in KwaZulu-Natal province prompts reactions in Zimbabwe, Malawi, Mozambique and Kenya as well.
Food and water have been scarce along the Omo River since work began on the Gilgel Gibe III project. The U.N. plans an assessment.
Malawi, Nigeria and Kenya are calling for the evacuation of their nationals amid continuing attacks in the city of Durban.
Many Africans were using cell phones to make payments long before it was cool in Europe and North America.
A new study found cell phones are now as common in South Africa and Nigeria as they are in the United States, but landline telephones are rare.
10 entrepreneurs -- addressing obstacles in education, infrastructure, health and other areas -- are finalists for an innovation prize.
"We thought it was another al-Shabab attack."
Kenya's deputy president says the country would change "the way America changed after 9/11," following an attack that killed 148 people.
The addition of rickshaws is one of many ways Uber is trying to compete in emerging markets around the world.
Civilians are caught in the middle as Kenya's government tries to cut off a Somali terrorist group's finances.
Kenya needs more help from its U.S. and European allies with intelligence and security measures to help prevent further massacres by Somali militants, Foreign Minister Amina Mohamed told Reuters on Tuesday.
Hundreds of Kenyan students marched Tuesday to honor those killed last week in the attack at Garissa University College in northeast Kenya.
The Kenyan air force has destroyed two al Shabaab camps in Somalia, it said on Monday, in the first major military response since the Islamist group massacred students at a Kenyan university last week.
The ongoing decline in tourism has hurt Kenya in recent years.