More than 28,000 Afghans have applied for temporary admission into the U.S. for humanitarian reasons since shortly before the Taliban recaptured Afghanistan and sparked a chaotic U.S. withdrawal, but only about 100 of them have been approved, according to federal officials.

U.S. Citizenship and Immigration Services has struggled to keep up with the surge in applicants to a little-used program known as humanitarian parole but promises it’s ramping up staff to address the growing backlog.

Afghan families in the U.S. and the immigrant groups supporting them say the slow pace of approvals threatens the safety of their loved ones, who face an uncertain future under the hard-line Islamic government because of their ties to the West.

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“We’re worried for their lives,” says Safi, a Massachusetts resident whose family is sponsoring 21 relatives seeking humanitarian parole. “Sometimes, I think there will be a day when I wake up and receive a call saying that they’re no more.”

The 38-year-old U.S. permanent resident, who asked that her last name not be used for fear of retribution against her relatives, is hoping to bring over her sister, her uncle and their families. She says the families have been in hiding and their house was destroyed in a recent bombing because her uncle had been a prominent local official before the Taliban took over.

The slow pace of approvals is frustrating because families have already paid hundreds if not thousands of dollars in processing fees, says Chiara St. Pierre, an attorney at the International Institute of New England in Lowell, Massachusetts, a refugee resettlement agency assisting Safi’s family.

Each parole application comes with a $575 filing charge, meaning USCIS, which is primarily fee-funded, is sitting on some $11.5 million from Afghans in the last few months alone, she and other advocates complain.

“People are desperate to get their families out,” said St. Pierre, whose nonprofit has filed more than 50 parole applications for Afghan nationals. “Do we not owe a duty to the people left behind, especially when they are following our immigration laws and using the options they have?”

Victoria Palmer, a USCIS spokesperson, said the agency has trained 44 additional staff to help address the application surge. As of mid-October, the agency had only six staffers detailed to the program.

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Of the more than 100 approved as of July 1, some are still in Afghanistan and some have made it to third countries, she said, declining to provide details. The program typically receives fewer than 2,000 requests annually from all nationalities, of which USCIS approves an average of about 500, according to Palmer.

Part of the challenge is that humanitarian parole requires an in-person interview, meaning those in Afghanistan need to travel to another county with an operating U.S. embassy or consulate after they’ve cleared the initial screening. U.S. officials warn it could then take months longer, and there’s no guarantee parole will be granted, even after the interview.

Humanitarian parole doesn’t provide a path to lawful permanent residence or confer U.S. immigration status. It’s meant for foreigners who are unable to go through the asylum or other traditional visa processes, but who need to leave their country urgently.

The backlog of parole requests comes on top of the more than 73,000 Afghan refugees already evacuated from the country as part of Operations Allies Welcome, which was focused on Afghans who worked for the U.S. government as interpreters and in other jobs.

Most have arrived in the country and have been staying on military bases awaiting resettlement in communities across the country, though about 2,000 still remain overseas awaiting clearance to enter the U.S., according to Palmer.

But advocates question some of USCIS’s recent decisions for Afghan humanitarian parole, such as prioritizing applications from those already living in other countries. They say that approach is at odds with the program’s purpose of helping those most at risk.

The Biden administration should instead focus on applications from women and girls, LGBTQ people and religious minorities still in the country, said Sunil Varghese, of the New York-based International Refugee Assistance Project.

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It could also dispense with some of the financial documentation required for applicants and their sponsors, since Congress has passed legislation making Afghan evacuees eligible for refugee benefits, said Lindsay Gray, CEO of Vecina, an Austin, Texas-based group that trains attorneys and volunteers on immigration matters.

Palmer didn’t directly address the critiques but said the agency, in each case, determines if there’s a “distinct, well-documented reason” to approve humanitarian parole and whether other protections are available. USCIS also considers whether the person already has U.S. ties, such as a family member with legal status or prior work for the U.S. government, among other factors.

In the meantime, Afghans in the U.S. have little choice but to wait and fret.

Bahara, another Afghan living in Massachusetts who asked her last name be withheld over concerns for her family, says she’s been wracked with guilt for her decision to leave her country to attend a local university.

The 29-year-old boarded a plane on Aug. 15 just hours before the Taliban swept into the capital of Kabul, leading to one of the largest mass evacuations in U.S. history.

“It was my dream, but it changed completely,” said Bahara, referring to enrolling in a U.S. master’s degree program. “I couldn’t stop thinking about my family. I couldn’t sleep the first few weeks. All I did was cry, but it didn’t help.”

Bahara said her family is worried because Taliban officials have been paying unannounced visits to people like her father who worked with the U.S. government after the militant group was originally ousted from power by the U.S. following the Sept. 11, 2001, terrorist attacks.

An American family is now sponsoring her family for humanitarian parole, giving Bahara hope even as she grieves over her country’s current situation.

“I cannot believe how everything just collapsed,” said Bahara, who founded a children’s literacy program in Afghanistan. “All the achievements and hard work just added up to zero, and now people are suffering.”

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Baktash Sharifi Baki, a green-card holder who has been living in the U.S. since 2014, was compelled to take more drastic measures as Afghanistan quickly unraveled this summer.

The Philadelphia resident, who served as an interpreter for the U.S. government, traveled back in August in the hopes of shepherding his wife, daughter, mother and godson to safety.

But the family wasn’t able to board any of the final commercial flights out of Kabul. Baki has appealed to the U.S. government to allow them to board one of the charter flights that have recently resumed.

Meanwhile, a friend in Louisiana has offered to serve as the family’s sponsor for a humanitarian parole application, even covering the costly fees himself.

Baki and his family are staying for now with relatives in the northern city of Mazar-e-Sharif. But he worries his modest cash savings is dwindling just as the region’s harsh winter sets in and Afghanistan’s economic crisis is deepening.

“We are really facing a bad situation here,” Baki said. “We need to get out.”