The official US tally has not accounted for hundreds of American citizens who have been left behind in Afghanistan following a chaotic evacuation effort, rescue groups say.
Veteran-led rescue groups said on Sunday that the US estimate that no more than 200 US citizens were left behind in Afghanistan is too low.
It said there are also permanent legal residents with green cards who are now stranded in Afghanistan.
Mike Jason, who runs an ad-hoc rescue operation in Afghanistan, said the number of US citizens is much higher than 200, a figure he called misleading because it does not include their family members who may be green card holders as well.
Jason said his volunteer group has been in contact with 78 green card holders trapped in the country.
His group also identified 45 US citizens in the country but has documents on more than 250 family members stuck there with them.
Thus, the number of those stranded in Afghanistan rises to nearly 400, Jason said.
Some groups say they continue to be contacted by US citizens in Afghanistan who did not register with the US Embassy before it closed.
The groups said they were also contacted by others who were not included in previous counts because they were worried about leaving their loved ones behind.
"The fear is that nobody is looking for them,” said Howard Shen, spokesperson for the Cajon Valley Union School District in the San Diego area.
"They are thousands of miles away under an oppressive regime and we’re leaving them behind,” he said. "That’s not right.”
The Taliban, who now run the country, have said they will allow people with valid travel papers to leave Afghanistan.
The US and its NATO allies launched a joint military evacuation operation in recent weeks to speedily pull out foreign citizens and Afghan allies, as the Taliban toppled the Kabul government.
But the slow evacuation efforts brought daily mayhem at the Kabul airport as thousands of Afghan civilians and diplomats swarmed the airport to take evacuation flights.
US President Joe Biden came under heavy criticism over his administration’s hectic pullout from Afghanistan and his handling of the evacuations.
Biden, however, defended the operation as an "extraordinary success" on Tuesday, saying they pulled out more than 120,000 people from Afghanistan since the Taliban took control of the country on August 15.
“We completed one of the biggest airlifts in history," Biden said on Tuesday.
The US-led invasion of Afghanistan removed the Taliban from power 20 years ago, but it worsened the security situation in the country. The Taliban are now poised to run the country again.