FBI agents arrested a Rittman man on Friday for his alleged involvement in the riot at the U.S. Capital building in January of 2021.  Investigators say they were able to identify 38-year old Mason Porter through a photo taken by another rioter that showed Porter helping another person scale a wall at the Capital.  The FBI says Porter also posted pictures of himself at the riot on social media.  Porter has been charged with four misdemeanors, including disorderly conduct and knowingly entering a restricted building.