BBC News By Hilary Andersson Published image captionThere are hundreds of children in some of the tents At a US border detention centre in the Texan desert, migrant children have been living in alarming conditions - where disease is rampant, food can be dangerous and there are reports of sexual abuse, an investigation by the BBC has found through interviews with staff and children. In recent months, the US has seen a massive rise in migrants and asylum seekers from Central America. Violence, natural disasters and pandemic-related economic strife are some of the reasons behind the influx, experts say. Some have also suggested the perception of a more lenient administration under Democrat Joe Biden has contributed to the crisis, though the White House has urged migrants against journeying to the US border.