http://www.boer-war.com/Details2nd/Camps.html
Excerpt:

These camps had were originally set up for refugees whose farms had been destroyed by the British "Scorched Earth" policy (the burning down all Boer homesteads and farms to stop the aid of Boers). Then, following Kitchener's new policy, many women and children were forcibly moved to prevent the Boers from re-supplying from their homes and more camps were built and converted to prisons. This relatively new idea was essentially humane in its planning in London but ultimately proved brutal due to its lack of proper implementation. This was not the first appearance of concentration camps. The Spanish used them in the Ten Years' War that later led to the Spanish-American War, and the United States used them to devastate guerrilla forces during the Philippine-American War. But the concentration camp system of the British was on a much larger scale.

There were a total of 45 tented camps built for Boer internees and 64 for black African ones. Of the 28,000 Boer men captured as prisoners of war, 25,630 were sent overseas. So, most Boers remaining in the local camps were women and children, but the native African ones held large numbers of men as well. Even when forcibly removed from Boer areas, the black Africans were not considered to be hostile to the British, and provided a paid labour force.

The conditions in the camps were very unhealthy and the food rations were meager. The wives and children of men who were still fighting were given smaller rations than others. The poor diet and inadequate hygiene led to endemic contagious diseases such as measles, typhoid and dysentery. Coupled with a shortage of medical facilities, this led to large numbers of deaths — a report after the war concluded that 27,927 Boers (of whom 22,074 were children under 16) and 14,154 black Africans had died of starvation, disease and exposure in the concentration camps. In all, about 25% of the Boer inmates and 12% of the black African ones died (although recent research suggests that the black African deaths were underestimated and may have actually been around 20,000).

A delegate of the South African Women and Children's Distress Fund, Emily Hobhouse, did much to publicise the distress of the inmates on her return to Britain after visiting some of the camps in the Orange Free State. Her fifteen-page report caused uproar, and led to a government commission, the Fawcett Commission, visiting camps from August to December 1901 which confirmed her report. They were highly critical of the running of the camps and made numerous recommendations, for example improvements in diet and provision of proper medical facilities. By February 1902 the annual death-rate dropped to 6.9% and eventually to 2%
http://christhum.wordpress.com/2010/06/16/south-africa-and-the-british-concentration-camps/#more-862