Aug 5, 2014 Southside Pit Bull Seriously Mauls and Hospitalizes Boy in Critical Condition

UPDATE: Both the dogs have been identified as pit bulls and the owner has been found, but it is not known if the owner will be charged. (It's Chicago, where pit bulls prey on south and west side children regularly, so probably not)
Be sure to watch the video in the ABC 7 link.  It shows the pit bull acting like any dog that got out to have an adventure, but then, for no reason but its artificially selected, inbred instincts, attacks a child horrendously.

Chicago - Armani McKinnis was at a friend's birthday party when two stray dogs, a pit bull and a rottweiler, came down the street. 
Armani's handsome face before and after being mauled by a pit bull
The pit bull launched an unprovoked, uninhibited, off property attack on Armani for enjoyment.  
The pit bull acting friendly and wagging its tail when it sees the
the children and decides to go attack Arami.
A neighbor recorded the horror that played out on his phone where a human child is preyed upon like an animal.

Read more:
ABC 7 Chicago