Celebratory fireworks lit up the Kabul sky on Tuesday night on the first anniversary of the withdrawal of U.S. troops from Afghanistan, which the Taliban are marking as 'Freedom Day'.

The withdrawal, completed a minute before midnight local time on Aug. 30, came as the war-torn country was taken over by the Taliban, who had waged a 20-year insurgency against U.S.-led forces that invaded Afghanistan in October 2001 following the Sept. 11 attacks in New York.

"Fireworks with various and beautiful colours are going to be held to mark Freedom Day," Taliban spokesman Zabihullah Mujahid had said earlier on Tuesday.

The fireworks were accompanied by intense celebratory aerial firing in many areas of Kabul.

The de-facto Taliban government has also declared Wednesday a public holiday to mark the day, the labour ministry said.

The head of the U.S. Central Command had said back then that there was "a lot of heartbreak" associated with the departure. Having failed to anticipate the Taliban would prevail so quickly, Washington and its NATO allies were forced into a hasty exit.

The United States completed its military withdrawal from Afghanistan after a huge but chaotic airlift that cost the lives of 13 U.S. service members and left behind thousands of Afghans and hundreds of Americans still seeking an escape from Taliban rule.

Some have since been able to leave, but many others remain in Afghanistan, where the Taliban are looking to establish a fully-functional government that is recognised by the international community.

The Taliban also are now dealing with an insurgency of their own, led by the Afghanistan affiliate of the Islamic State militant group.

(Writing by Gibran Peshimam; editing by Jonathan Oatis)