According to the info in this article the Mom saw him leave in a SUV about 9 pm Friday and it wasn’t until about 3:30 pm Sat that the BPD got in touch with her with the news.
http://blog.al.com/spotnews/2012/05/slain_teen_jaquares_walkers_mo.html
I also find it interesting that the location of the incident is over 14 miles from the school he attended. In other words, it likely wasn’t the near neighborhood he lived in. That said, they may have planned way ahead of time on robbing that specific individual.