Y’know, some would say that children making a hazardous journey up the length of Mexico from other Central American countries without adult guidance, should be given the benefit of the doubt on this point.
Maybe some of these kids were from reasonably safe places, and were just out on an extended joyride. And if so, they should certainly be returned home if it is found that that is the case. But absent such knowledge, ISTM that the Christian approach would be to err on the side of mercy.