MILWAUKEE (CBS 58) -- Milwaukee activist Vaun Mayes has pleaded not guilty at the federal courthouse Wednesday. 

Mayes spoke briefly after his arraignment and plea hearing.

He faces five federal counts and is accused among other things of trying to firebomb a Milwaukee Police station during the Sherman Park unrest in the summer of 2016. 

Federal investigators have also said that associates of the 31-year-old tried to intimidate a witness.