What would you do if you saw this?

so across my house there is a house that has people that are mentally challenged and they have workers that come and watch them. i am not trying to be racist but the people that take care of them are African american. well i would always hear screaming from that house and i would here the workers saying f**k you and this and etc.. my mother and brother saw the workers pull on them like get there shirt and pull them towards them and my brother saw one of the workers pull a guy by his feet like dragging him. i want to go to the authorities or someone that is in charge of it but my mom said no what happens if they knew it was us, they could do something to us. i was like so you just want to site here and let that happen, what do u think i should do?