Minutes after ProPublica posted a recording of crying children begging for their parents, Kirstjen Nielsen stepped up to the podium in the White House briefing room to answer questions from reporters, as well as a growing chorus of criticism from Democrats and Republicans.

Nielsen, the Secretary of the Department of Homeland Security, blamed Congress for the Trump administration’s policy of separating children detained at the border from their parents. Nielsen said the administration would continue to send the children to temporary detention centers in warehouses and big box stores until Congress rewrites the nation’s immigration laws.

At one point, a reporter from New York magazine, Olivia Nuzzi, played the tape ProPublica obtained from inside a U.S. Customs and Border Protection facility, according to tweets she posted.

It’s unclear if Nielsen heard the recording, which consists mostly of the sounds of weeping children calling for their mothers and fathers. Reporters attempted to ask her questions about the material in the recording — including “How is this not child abuse?” — but she did not respond directly. Asked if the recordings, along with pictures and more that have emerged in recent days, are an unintended consequence of the administration’s approach, she said, “I think that they reflect the focus of those who post such pictures and narratives.”

Richard Tofel, ProPublica’s president, said the decision to post the recording and accompanying story reflected a focus on providing a fuller accounting of what’s happening in facilities that are closed to public view.

“Our agenda is to bring the American people facts for their consideration,” he said.

The separation of these Central American children from their parents was triggered by the administration’s decision to bring criminal charges against adults who enter the country without permission. That move, which is discretionary, brings into play regulations that prevent parents facing criminal prosecution from being imprisoned with their children.

Nielsen denied that the policy change was intended to pressure Congress.

“The children are not being used as a pawn,” she said. “We’re trying to protect the children, which is why I’m asking Congress to act.”