Nonprofit news organization ProPublica has obtained audio from inside a U.S. Customs and Border Protection facility, in which children can be heard wailing as an agent jokes, “We have an orchestra here.”

The story about the audio was written by Ginger Thompson, a senior reporter at ProPublica. A Pulitzer Prize winner, Thompson previously spent 15 years at The New York Times, including time as a Washington correspondent and as an investigative reporter whose stories revealed Washington’s secret role in Mexico’s fight against drug traffickers.

Thompson’s story starts:

The desperate sobbing of 10 Central American children, separated from their parents one day last week by immigration authorities at the border, makes for excruciating listening. Many of them sound like they’re crying so hard, they can barely breathe. They scream “Mami” and “Papá” over and over again, as if those are the only words they know.

The baritone voice of a Border Patrol agent booms above the crying. “Well, we have an orchestra here,” he jokes. “What’s missing is a conductor.”

Then a distraught but determined 6-year-old Salvadoran girl pleads repeatedly for someone to call her aunt. Just one call, she begs anyone who will listen. She says she’s memorized the phone number, and at one point, rattles it off to a consular representative. “My mommy says that I’ll go with my aunt,” she whimpers, “and that she’ll come to pick me up there as quickly as possible.”

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