Khartoum March 1884, troops loyal to the Mahdi Muhammad Ahmad started a siege of Khartoum, against defenders led by British General Charles George Gordon. The siege ended in a massacre of the Anglo-Egyptian garrison when on 26 January 1885 the heavily-damaged city fell to the Mahdists. On 2 September 1898, Omdurman was the scene of the bloody Battle of Omdurman, during which British forces under Herbert Kitchener defeated the Mahdist forces defending the city. In 1973, the city was the site of an anomalous hostage crisis in which members of Black September held 10 hostages at the Saudi Arabian embassy, five
Khartoum Bridge (finished in October 2007) and the Tuti Bridge that links Khartoum to Tuti Island. In the 21st century, Khartoum developed based on Sudan's oil wealth (although the independence of South Sudan in 2011 affected the economy of Sudan negatively). The center of the city has tree-lined streets. Khartoum has the highest concentration of economic activity in the country. This has changed as major economic developments take place in other parts of the country, like oil exploration in the South, the Giad Industrial Complex in Al Jazirah state and White Nile Sugar Project in Central Sudan, and the Merowe Dam