BANG! BANG! BANG!
Drop the gun!
As a homeowner thats been involved int his, you dont know how many others were with the one guy, you don know where they are, if they are waiting to attack you, regrouping, you cant ever assume its over until thorough searches are done.
And hopefully the cops dont blow you away while you are defending yourself.
This is why i would hesitate to get involved with helping a cop in a gunfight. They could very well assume the worst about you and then youre dead.
Put it down. Keep it nearby in case it’s required again. Friendly fire could be an issue also with armed school personnel.