NEW : Legislators clash at a House hearing where victims of targeting appeared . The FBI has been investigating the Russian hacking for months and issued an alert in October to state election officials about their systems being targeted. Congress , the IRS , the inspector general and the Justice Department are investigating . The GOP House Appropriations chairman evokes Nixon in warning of an enemies list .
NEW : Legislators clash at a House hearing where victims of targeting appeared . As Congress probes IRS targeting , the two parties offer varying takes on what happened . Congress , the IRS , the inspector general and the Justice Department are investigating . The GOP House Appropriations chairman evokes Nixon in warning of an enemies list .