Although the cause of a fire that destroyed the town hall building in Register Sunday was ruled “undetermined,” a $10,000 reward is offered for information leading to the arrest of anyone who is proven guilty of arson. A caller reported the fire around 3:50 a.m. Sunday to Bulloch County 911, said Bulloch County Public Safety Director Ted Wynn. The fire was “called in as electrical” by a person who has not been identified to the public, he said.