I agree with the first few in succession sounded like gun shots to me, too. But from 13-15 second mark, you can kind of hear the firework splash at the end if your turn the volume up.
Sounds like maybe sixteen or seventeen pops and some echoes in there . . . maybe a full-capacity 9mm pistol like two of mine. And on a weekend morning when the yahoos are busier than normal.
I also thought the first 4 or 5 sounded more like gun shots. After that it gets trickier, could be different weapons or multiple weapons or various fireworks / firecrackers.
It's worth noting that fireworks are more likely to set off a car alarm than gun shots. Of course if someone driving was shot and drove into a parked car that could be the car alarm.