The Lamar County courthouse was evacuated at 9:45 a.m. Monday after crews installing new heating and air conditioning equipment ran afoul of a gas line. The courthouse was packed for a probate court hearing day. A long criminal trail calendar is to be heard Tuesday.Capt. Chris Webster of the LCSO, who runs courtroom security, said the probate court hearings were put off until January. He epected courthouse employees to return to their stations when firefighters adequately ventilated the aging building.