Smithfield — Police here have arrested a Zebulon man for setting two fires in one day, according to authorities.Justin Dale Gray, 18, of 10633 N.C. 96, is suspected of setting the fires Feb. 26 at Ed Stephenson’s barn across from Smithfield-Selma High School. Gray was taken into custody at 7:59 p.m. Thursday at the Smithfield Police Station. His bond was set at $80,000, according to a report.