Washington (CNN) Acting Homeland Security Secretary Kevin McAleenan said Sunday that officials are "concerned" about how the "average hours in custody is increasing" for migrant children at the southern border and that additional funding the Trump administration wants from Congress would help combat the issue of overcrowding at processing facilities.

"I think what we're concerned about is the average hours in custody is increasing. That's why (the Department of Health and Human Services) needs this funding," McAleenan told CNN's Jake Tapper on "State of the Union." "They need to be able to buy additional beds, especially for teenage males, which is the number one demographic that's crossing right now unaccompanied as children. We need to be able to move people very quickly to HHS custody -- to a better situation." p

The comments come several days after DHS' Inspector General found "dangerous overcrowding" and unsanitary conditions at an El Paso, Texas, Border Patrol processing facility following an unannounced inspection. According to the IG's assessment, reported exclusively by CNN, logs indicated that on May 7 and 8 there were "approximately 750 and 900 detainees, respectively" at the Texas facility, which has a maximum capacity of 125 migrants.

Last month, McAleenan said a supplemental budget request was coming that would seek funding for temporary and semi-permanent migrant processing facilities, additional personnel along the border, increased detention capacity and upgrades to "overtaxed" information technology systems.

McAleenan, who told Tapper that the number of illegal border crossings increased in May, said the additional funding would "provide better care for people in our facilities," adding that DHS is working with the Department of Defense to mitigate overcrowding.

"They're going to help us with 7,500 additional spaces to prevent people from being too crowded in our facilities," he said. "We've already put up 1,000 temporary facility spaces on the border in Texas. We're going to add Arizona this month. We're driving as hard as we can to provide a better scenario."