(AP) — A school district in a San Diego suburb that is home to a large refugee population said many of its families who had taken summer trips to Afghanistan to see their relatives have gotten stuck there with the chaos following the withdrawal of U.S. troops.

The Cajon Valley Union School District, in the suburb of El Cajon, east of San Diego, said the families of 24 students from various schools had reported they would not able to start the school year on Aug. 17 because the children and their parents were unable to get through the throngs of people at the Kabul airport. Thousands of people have been converging on the airport, desperate to escape since the Taliban seized control of the country.

The families had traveled separately to Afghanistan for summer vacations to see their grandparents, cousins and other relatives. Most of the families came to the United States on a special immigrant visa after having worked for the U.S. government in Afghanistan, officials said. The visa allows only the former government employee and immediate family to come to the United States.

“Just like you and I, they had used the summer to go back to see their relatives,” Superintendent David Miyashiro said. “No one felt that were going to be unsafe or unable to return.”

He added that the families are particularly scared because of the upcoming Aug. 31 deadline for the United States to end its withdrawal.

Many of the families left in early May and June, months before the crisis unfolded and the president of Afghanistan fled as the Taliban seized power, officials said.

The district has been in direct contact with the families and was working with Republican Rep. Darrell Issa’s office to try to help get them out safely. The children range from preschoolers to high school students.

Jonathan Wilcox of Issa’s office said in an email to the San Diego Union-Tribune that the congressman and his staff “were working diligently to determine the facts on the ground, any bureaucratic barriers that can be removed, and the best ways to help those stranded leave Afghanistan and return home safely.”

“We won’t stop until we have answers and action,” he wrote.

Officials became aware of the problem after getting a call from a relative of one of the students on Aug. 16, a day before the school year was to begin, to report that the child would be absent and ask officials to hold their spot.

Miyashiro said the 24 students attend different schools in the district. He said he could not provide more details since the children and their parents could be in danger.

“It’s killing us right now,” Cajon Valley school board president Tamara Otero told the newspaper. “We are so worried about our students that are stuck there. We’ll do the best we can to get them out.”