Who are the Central American children fleeing to the US border?

TO SEE VIDEO:

http://www.bbc.com/news/world-us-canada-28589121

2 hours ago

The unaccompanied children fleeing Central America to the United States keep coming - and America's politicians have yet to agree on how to handle the influx.

Meanwhile, an analysis of US government data by the Pew Research Center found that children 12 and under are the most rapidly growing group of minors being apprehended at the border.
The data shows a 117% increase among these minors when compared to the same group in the last fiscal year.
So what else does the data tell us? The BBC's David Botti looks through the numbers.