They attack.

I don't believe you'll be able to smash it. They look like stone, but they really aren't. And it is human instinct to flinch and blink when striking something that can shatter. At that range the instant your eyes closed, it would bee too late. They will have moved and likely reached you.

I can't hazard to guess what the result of such an attack would be here in the City, but back home, it isn't something most people would like.