Gems, al-Qaida and murder. Mystery over killing of Osama Bin Laden's friend · Saudi man's death was political, say his family· US secret service was monitoring his activities Nick Fielding Friday March 2, 2007 The Guardian (UK) Pallbearers carry the coffin of Muhammad Jamal Khalifa at Ivato airport in Antananarivo, in Madagascar. Photograph: Jasleen Sethi/Reuters When Muhammad Jamal Khalifa was found dead at a remote gemstone mine in south-eastern Madagascar at the end of January, local police quickly put the murder down to a business deal gone wrong. The Saudi businessman, 49, had had to call in local police to...