(CNN) -- The mastermind of the worst terrorist attack on American soil is dead, U.S. President Barack Obama announced late Sunday night, almost 10 years after the attacks that killed almost 3,000 people.
Osama bin Laden -- the longtime leader of al Qaeda -- was killed by U.S. forces in a mansion outside the Pakistani capital of Islamabad along with other family members, a senior U.S. official told CNN.