Police spokesman Jeremy Lewis told a press conference that Nolen's colleagues had said "he recently started trying to convert several employees to the Muslim religion".
However, it is not clear if his beliefs had any link to the attack. The FBI is also investigating the incident. [emphasis mine]
Oklahoma Beheading: Fired Man's Knife Rampage
The suspect, who had just lost his job, was stabbing a second female employee when he was shot by the boss.
Video: Nolen in a previous mugshot. Pic: Oklahoma Department of Corrections
A man who had just been sacked at an Oklahoma food plant decapitated one female worker and stabbed another before he was shot and wounded by the boss.
Police said Alton Nolen, 30, was "angry" after losing his job when he launched into a knife rampage at Vaughan Foods in Moore on Thursday afternoon.
Mark Vaughan, chief operating officer of the business and also a reserve police officer, is being hailed as a hero after he shot Nolen while the suspect was stabbing a second woman.
Authorities say it appears Nolen targeted the workers at random.
The attack began at about 4pm when he went to the car park and drove his vehicle to the front of the warehouse where he hit another car.
Nolen then walked through the main entrance and began his rampage.
Police spokesman Jeremy Lewis told a press conference that Nolen's colleagues had said "he recently started trying to convert several employees to the Muslim religion".
However, it is not clear if his beliefs had any link to the attack. The FBI is also investigating the incident.
The first victim has been identified as 54-year-old Colleen Hufford.
Mr Lewis told Friday morning's press conference: "He did kill Colleen and he did sever her head."
Nolen and the second victim, 43-year-old Traci Johnson, are both in a stable condition in hospital, said police.
Mr Lewis praised Mr Vaughn's swift action.
"It could have gotten a lot worse," he said. "This guy (Nolen) was definitely not going to stop."
There were said to be several hundred employees inside the warehouse at the time of the attack.
According to the state department of corrections, Nolen was convicted in 2011 of marijuana possession, intent to distribute cocaine, escape from detention and assault on a police officer.
Vaughan Foods spokeswoman Danielle Katcher said everyone at the company was "shocked and deeply saddened" by Thursday's attack.
"Our thoughts and prayers go out to the families and friends of the team member we lost and all those affected," said her statement.
Employees would be offered counselling, she added.
