A motorist driving on I-580 called to report a male standing on the platform pointing a rifle at the freeway. The caller provided a description of the male suspect and said that the rifle appeared to have a scope. Alameda County Deputies and BART Officers conducted a hazardous train search of the train that was held on the platform and located a suspect matching the description. The suspect had only an umbrella in his possession. He was identified and released. The trains were held for 12 minutes for the response/search.