Anxiously awaiting updates. Two notable points from Fox article - bbm:
Police calling the crime "unusual," and said the
crime scene extends about 200 feet back into a bike trail and includes a wooded area behind some homes.
...
Police believe the boy’s family lives in the neighborhood.
A parent of the child has been notified, however it’s still unclear if the child was reported missing.
Dallas police investigating murder of child
JMO: Umm... they were going door to door asking if the families were missing a child, so it seems unlikely the child had been reported missing.