Oklahoma plans to file a murder charge as early as Monday against Alton Nolen, who is suspected of beheading a former co-worker at a food distribution center last week, officials said.
The Federal Bureau of Investigation is also looking into Nolen's background for any potential religious ties to the attack after former colleagues said he had attempted to convert them to Islam. Police said Nolen had recently become a Muslim.
Nolen, 30, is suspected of attacking two women shortly after being fired on Thursday at Vaughan Foods in Moore, a suburb of Oklahoma City, police said.