Perhaps a long horned beetle
https://www.google.com/search?q=long+hor...
You didn't give much discription so it is a shot in the dark. The other thing I thought of was a giant water beetle.
https://www.google.com/search?q=long+hor...
Today i was attacked by a Beetle about six inches long that was black with silver-like lines running along it's body, and had what looked like a hard shell. When it saw me it immediately started flying at me. Buzzing me and harassing me. Then when I came back a few minutes later it saw me again and attacked again. Like it was protecting it's territory. I was unable to catch it or kill it because it was to fast for me. It brushed against my bare leg, but the area doesn't seem affected. If any one can tell me what it is that would be great. I've lived here all my life and have never seen such an insect.
I live In central Arkansas, United states. If you need more information please feel free to ask.
