I know about a dog fight event going down soon,not sure what to do?

one of my friends told me about a dog fight event going down these weekend and he wants me to go with him. not gonna lie,i've always wondered what they're like,but i know i would feel really guilty about going. i don't know if i should tell the police or not,because here in harlem if someone finds out you talked to the police you could get killed for it. also,most of these underground dog fights ae run by very dangerous people,and this is one of the ways they make money by hosting dog fights. you guys think i should just not go,and forget about or risk my life and tell the police about it?