The U.S. officially ended its military presence in Afghanistan on Tuesday with the final flight out of Kabul, concluding two decades of American involvement touched off by the Sept. 11 terrorist attacks.

"I’m here to announce the completion of our withdrawal from Afghanistan and the end of the military mission to evacuate American citizens, third-country nationals and vulnerable Afghans,” Gen. Kenneth McKenzie, the head of U.S. Central Command, said Monday afternoon in the U.S. "The last manned aircraft is now clearing the airspace above Afghanistan.”

America’s longest war ended with a rushed withdrawal of more than 123,000 people since Aug. 14. That followed the Taliban advance to Kabul, and the killing of 13 U.S. service members in a suicide bombing outside the capital city’s airport last week.