The elite group, which was trained for counterterrorism missions and collaborated with US intelligence agencies for years, assisted the US forces to evacuate more than 2,000 American citizens and permanent residents, as well as around 5,550 local embassy staffers, third-country nationals and Afghans at risk of Taliban reprisal.
"They were extraordinarily well trained, and when, frankly, the regular army was dropping their weapons and running away, they were running into the breach," a senior US administration official told the newspaper, adding that most of the special forces deployed in southern Afghanistan had to "fight their way" to Kabul to help the evacuation operation.
The Taliban have identified some members of the elite group and sent them text messages with threats to kill them and their families, the news outlet added.
The Washington Post did not specify the exact number of these elite group members stranded in Afghanistan but noted that the resettlement process was inordinately bureaucratic and slow.
Following the Taliban takeover, a number of countries began evacuating their citizens and diplomatic missions from Afghanistan, and some have promised help to their Afghan collaborators.
*A terrorist group outlawed in Russia and many other countries.