State Department Deputy Secretary Wendy Sherman at a briefing on Wednesday said the U.S. is executing an “all hands on deck effort” to get Americans and Afghans to the airport in Kabul for evacuation flights amid reports that Taliban fighters are stopping individuals at checkpoints.

Presented with the U.S. embassy’s recent alert informing Americans the U.S. "cannot provide safe passage"

“That was one of the most searing meetings I have had as a diplomat,” she said. “A young teenager told me about watching her sister~,~ being raped and thrown out the window. Women who were doctors and teachers and homemakers talked about how they couldn't do anymore.”

Sherman also directly addressed the fate of women and girls, saying the issue is “personal” to her since she met with Afghan women and girls during diplomatic work in 1997, when the Taliban enforced a strict interpretation of Sharia or Islamic law in Afghanistan.

“That was one of the most searing meetings I have had as a diplomat,” she said. “A young teenager told me about watching her sister, being raped and thrown out the window. Women who were doctors and teachers and homemakers talked about how they couldn't do anymore.”

“That memory will never be wiped from my mind,” Sherman said, before tossing the first question to a woman reporter from Afghanistan.

The State Department has directed American citizens to the airport in Kabul for departing evacuation flights -- but with a stark warning.

"The United States government cannot ensure safe passage to the Hamid Karzai International Airport," the agency said in an alert to American citizens still in Afghanistan.

"The security situation in Kabul continues to change quickly, including at the airport," read an email notice from the U.S. Embassy in Kabul.

As many as 11,000 Americans and tens of thousands of Afghans are still desperately trying to leave the country, ABC News Senior Foreign Correspondent Ian Pannell has reported.

-ABC News' Cindy Smith

Pentagon press secretary John Kirby confirmed to reporters that Biden and Vice President Kamala Harris received a briefing on Afghanistan at the White House on Wednesday.

The White House said the group, which also included Secretary of State Antony Blinken, National Security Adviser Jake Sullivan, Commander of U.S. Central Command Gen. Kenneth McKenzie and CIA Director William Burns, discussed "efforts to accelerate evacuations" and "to facilitate safe passage to HKIA [Hamid Karzai International Airport]."

The readout from the White House also said the group discussed "monitoring for any potential terrorist threats in Afghanistan."

-ABC News' Sarah Kolinovsky

A senior U.S. intelligence official acknowledged to ABC News that the "rapid collapse" of the Afghanistan government "unraveled even more quickly" than U.S. intelligence officials had anticipated.

“We consistently identified the risk of a rapid collapse of the Afghan government. We also grew more pessimistic about the government’s survival as the fighting season progressed. This was less an issue of Afghan military capabilities and more a reflection of Afghan leadership, cohesion and willpower," the official told ABC News. "That said, the Afghan government unraveled even more quickly than we anticipated.”

Afghanistan's President Ashraf Ghani and his family fled Kabul on Sunday as the Taliban moved closer to the presidential palace and then claimed the formation of the "Islamic Emirate of Afghanistan."

-ABC News' Cindy Smith