Trying to read between the lines, it appears that an individual who was a member of a gang recognized another individual who was member of another gang and they started firing at each other - as opposed to a gang-planned event. It also feels like they have a good idea of who was involved, they just need to find those people. Unfortunately, if you live near I-95 anywhere in the South, there is gang activity related to the drug trade.
I am aware of many events where a gang member recognizes an enemy and immediately begins firing with absolutely no concern for bystanders.