Alton Nolen, 30, is due to be charged today with first-degree murder, as well as assault and battery with a deadly weapon. He may also face federal charges.
It was after being fired from his job at the Vaughan Foods in an Oklahoma City suburb that Nolen went on a frenzied knife rampage Thursday, severing the head of a colleague and wounding another before being shot by his former boss.
The incident came in the wake of a series of beheadings of Western captives by militant fighters in the Middle East and Algeria, but US officials have not confirmed any link to the Oklahoma case. Nolen had recently converted to Islam.
"His family, our hearts bleed right now because what they saying Alton has done," Nolen's mother said in the short video statement, sitting next to her daughter Megan.
More From This Section
"I want to apologize to both families -- because this is not Alton."
In a separate Facebook entry, Megan Nolen said her brother "has been a great influence to me and has always been a loving and caring person."
"He has never been a violent person and has never done any physical harm to anyone. Only God knows why what happened took place," she added.
"I am praying for the families as well as for my brother."
On Facebook, Nolen went by the moniker Jah'Keem Yisrael. He posted photographs of the World Trade Center towers going up in smoke during the September 11, 2001 attacks and of graves.
In another post in May disparaging Americans who eat pork, women who don't cover their hair and gays getting married, he warned that "SHARIA LAW IS COMING!!!!!!"
His account shows he has 1,470 "friends," many of them women wearing the Muslim veil.