Police in Red Oak early this (Friday) morning, arrested a Union County man on a Cass County warrant. Authorities say 21-year old Jordan Thomas McElroy, of Creston, was arrested at the corner of Highway 34 and G Avenue at around 2:15-a.m.   He was taken into custody on a valid Cass County warrant for felony Violation of Probation, and brought to the Montgomery County Jail, where McElroy was unable to post a $2,000 cash bond. He was later transported to Atlantic and held in the Cass County Jail.