BAGHDAD (Reuters) - The Iraqi official heading the investigation into alleged corruption in the United Nations oil-for-food program was killed in a bomb attack earlier this week, officials familiar with the probe said on Saturday. Ihsan Karim, head of the Board of Supreme Audit, died in hospital after a bomb placed under one of the cars in his convoy exploded on Thursday, the officials said. Iraq's former U.S. Governor Paul Bremer gave the board independence from the executive branch of government and appointed Karim as its head in April. The board appointed international accountants Ernst and Young in May to...