A US businessman has said he told federal investigators the location of Osama bin Laden's compound in Pakistan years before his killing and is seeking a $25 million (£15.7 million) reward.

A letter obtained by The Associated Press from a Chicago-based law firm representing Tom Lee, 63, says the gem merchant reported the location of the al-Qaeda leader's compound in Abbottabad in 2003.

The letter, sent to FBI director James Comey in August, says a Pakistani intelligence agent told Lee he escorted bin Laden and his family from Peshawar to Abbottabad.

Lee reported that the Pakistani agent "was a member of a family that Lee had done business with for decades", and that the agent and his family opposed bin Laden.