The Department of Homeland Security will not let members of Congress talk with the Customs and Border Protection agents who detained a 7-year-old migrant child before she died earlier this month, BuzzFeed News reported Monday.

According to the news outlet, DHS denied access to members of the Congressional Hispanic Caucus who will travel Tuesday to visit the remote station where Jakelin Caal Maquin was first treated.

At one point in the Monday conference call in which DHS denied the request, Rep. Joaquin Castro, D-Texas, warned the department it could expect the agents to be called before Congress as soon as Democrats take control of the House in January, BuzzFeed News reported.

DHS spokesperson Katie Waldman defended the department's refusal, however, noting an ongoing investigation and top Border Patrol officials have already been made available, BuzzFeed News reported.

She also told lawmakers it is the role of the DHS's inspector general, not Congress, to investigate, and Customs and Border Protection cannot force its unionized agents to talk to lawmakers.

Meanwhile, the girl's father, Nery Gilberto Caal, has denied Trump administration claims his daughter was without food or water for several days before they arrived at the border Dec. 6; she died less than 30 hours after illegally crossing into the United States, the news outlet reported.