washington federal state authorities beef cyber defenses potential electronic attack vote systems ahead u.s. elections nov. take new step guard possible civil unrest violence threat computer hack potential violent clash darken already rancorous presidential race democrat hillary clinton republican donald trump amid fear russia actors could spread political misinformation online perhaps tamper vote counter cyber threat two u.s. state accept help u.s. department homeland security dhs probe scan voter registration election systems vulnerabilities department official tell reuters ohio ask cyber protection unit national guard reserve force within u.s. military assistance protect state systems thursday arizona secretary state michele reagan cyber security team meet officials fbi dhs addition state-level agencies discuss cyber threats say matt roberts spokesman reagan national governors association friday say election officials well prepare possible cyber threats confront decade remain confident technical problems election night undermine overall integrity process association say statement unidentified intelligence officials tell nbc news thursday specific warn election day attack remain concern hackers russia elsewhere may try disrupt process likely spread misinformation social media sit potential violence around election loom background campaign months arm group around country pledge unprecedented number monitor vote sit sign election fraud federal officials warn authorities new york texas virginia unspecific threat attack al qaeda militant group around election day put local law enforcement alert tuesday vote u.s. government source washington say federal agencies send bulletin local state officials flag information threat relatively low level continue high level patrol facilities place time say spokesman steve coleman port authority operate airports tunnel bridge around area voter intimidation report poll sit far prompt democrats accuse trump campaign vigilante voter intimidation four state monday local authorities survey reuters thursday five state ohio pennsylvania arizona wisconsin florida say increase election-related law enforcement personnel resources 2012 level fbi designate one special agent 56 field offices election crime matter increase number give staff additional train year say fbi spokeswoman substantive change number personnel deploy rest justice department designate assistant u.s. attorneys federal prosecutors within agency public integrity section handle election crimes accord spokesman jim pasco executive director fraternal order police represent hundreds thousands u.s. officer say cop take security measure would take large event say expect vow militias monitor poll lot talk little action u.s. bolster cyber defense election new step violence