A fired Oklahoma food processing plant worker who had tried to convert some of his co-workers to Islam beheaded one co-worker and seriously injured another before the owner of the plant shot him, police said Friday. After he was terminated from Vaughan Foods in Moore, Alton Nolen, 30, drove to another part of the facility where he attacked Colleen Hufford, 54, police said. He used a “standard” knife to behead her, police said. He then allegedly used the same knife to repeatedly stab Traci Johnson, 43. Some co-workers told police that he had recently converted to Islam and had been trying to convert them. Police said Nolen had no relationship with either victim. Sources told NBC News there was no indication he had been in contact with terrorists groups such as ISIS.