I was walking down Spring Park from Centre at almost exactly that time and kids were lighting off fireworks. Not right on SP Ave, but somewhere just off of it like Chestnut. I am pretty sure that this was not gunplay.
Agree that it sounded like fireworks. I live on Chestnut Ave -- I was up late and heard the sharp noises -- sounded more like old fashioned midwestern firecrackers than gunshots, though I confess I'm more familiar with the sound of the former than the latter.