CCTV Footage of Karachi Bomb Aftermath

Description: Pakistan's largest city has had a history of violence in recent years. One major cause - sectarian disputes between majority Sunni and minority Shia Muslims - regularly rears its head. In recent years there has been a spate of shootings, some of them sectarian, which have left many dead. In 2002, there was a shoot-out between police and suspected al-Qaeda militants; two bomb attacks on foreigners, an alleged militant attempt on the life of President Pervez Musharraf, and the kidnapping and killing of US journalist Daniel Pearl. And it was to Karachi that a journalist from the Arabic al-Jazeera television network was invited to interview two top al-Qaeda leaders. The fact that al-Qaeda men were in Karachi rather than holed up in a tribal area may surprise some. But in fact correspondents say militant suspects are probably less conspicuous in Karachi than even among sympathetic tribal groups in the north. It was in 2002 that Yemeni national Ramzi Binalshibh, who claimed to have been one of the organisers of the 9/11 attack on the US, was captured after a three-hour gun battle at an apartment in Karachi. Karachi is a densely populated port city, bursting at the seams. A 1998 census put the population at just under 10 million - but a more realistic figure is probably over 16 million. The population is multi-ethnic, with about 500,000 new economic migrants arriving in the city every year - not just from the other provinces but also from neighbouring countries like Afghanistan, Bangladesh, Nepal and Sri Lanka.