fired Oklahoma food processing plant employee who proselytized for Islam beheaded a co-worker and seriously injured another before the owner of the plant shot and wounded him, police said Friday. Moments after Alton Nolen, 30, was let go from Vaughan Foods in Moore, he drove to another part of the facility and walked into a front office where he attacked 54-year-old Colleen Hufford, police said.

He used a "standard" knife — similar to the ones found at the facility — to allegedly behead Hufford. Then, he used the same knife to repeatedly stab Traci Johnson, 43, who suffered numerous wounds and remained in stable condition Friday, police said. "He obviously was trying to kill her, too," Moore police Sgt. Jeremy Lewis said at a news conference. He added that Nolen had no relationship with either victim, who were simply in his way when he flew into a rage.

Mark Vaughan, who is both the company's president and chief operating officer and a reserve deputy with the Oklahoma County Sheriff's Office, shot Nolen as he attacked the second victim. Nolen was taken to the hospital, where he is expected to survive. Police say that once he becomes coherent he will be interviewed and charged.

Oklahoma County Sheriff John Whetsel said there was "every reason to believe" others would have been targeted if Vaughan had not intervened.

"I am extremely proud of the actions of Deputy Vaughan and I am convinced those actions saved the lives of several other employees," the sheriff said in a statement.

The circumstances of Nolen's firing weren't made public. Some co-workers told police that he had recently converted to Islam and had been trying to convert them. Law enforcement officials told NBC News that his conversion took place during his recent stint in prison, which ended in March 2013, records show. A search of his home and car didn't immediately yield any connection to radical fundamentalism, and there's no indication he had been in contact with terrorist groups such as ISIS, sources said.

Local authorities are working with the FBI to do an extensive background investigation, Lewis said. Law enforcement officials say they are looking into his online activities and whether a Facebook page that contains materials with terrorist and fundamentalist themes was maintained by Nolen under an alias. Nolen does have an extensive rap sheet, including assault and battery on a police officer and escape from detention, according to NBC station KFOR of Oklahoma City.

Moore, south of Oklahoma City, was the scene of a monster tornado last year that flattened parts of the town and killed two dozen people.