VIDEO: Two people were killed and several others injured in a late Wednesday explosion and fire at a corn milling plant in Columbia County. One of two employees who had been missing was found dead about 5:50 p.m. Thursday. A search and rescue mission continued Thursday night for the other employee who had been on shift at the Didion Milling plant on Highway 146 in Cambria who was still missing as of 7:45 p.m. Thursday, Sheriff Dennis Richards said during a news conference.