The number of unaccompanied migrant children in US custody is growing by roughly 500 per day, with some 5,000 minors currently housed in “temporary facilities” at the border, many of them well beyond the legal 72-hour limit.

Roughly 10,500 unaccompanied children are held in “licensed” migrant shelters, suitable for longer-term care for minors, Department of Health and Human Services spokesperson Mark Weber told CBS News on Saturday.

But in the meantime, authorities are struggling to find space for another 5,000 kids, held by Customs and Border Protection inside a tent camp in Texas and other temporary facilities along the Mexico border.