The official said that Bin Laden was dead, but did not provide details of how his death occurred.
US media quoted sources as saying that Bin Laden was killed in an operation based on actionable US intelligence targeting a mansion outside Islamabad.
Obama was imminently to address Americans in a highly unusual Sunday night appearance on television.
The death of Bin Laden will raise huge questions about the future shape of al Qaeda and also have steep implications for US security and foreign policy 10 years into a global anti-terror campaign. (AFP)