Alton Nolen: A jihadist beheading in Oklahoma?

An Oklahoma man accused of beheaded his co-worker with a knife on Thursday is to be charged with murder. But it's still unclear whether the alleged attack was carried out in a wild fury, as a response to being fired, or whether it was an act of jihad.

On the highway outside the Vaughan Foods processing plant in the suburban town of Moore, on the edge of Oklahoma City, a small memorial of yellow flowers and American flags has appeared.

It marks the violence that took place here last week, when police say Alton Nolen took his work knife and used it to behead one woman and seriously injure another.

What first appeared to be a horrific example of an angry employee "going postal" took an unexpected turn when police said Nolen had been trying to convert his workmates to Islam in the weeks before the crime.

"We have a lot of problems with tornadoes, but we don't tend to have problems like this," says Phil Harris, a massage therapist, expressing the shock felt throughout Moore's 55,000-strong population.

As more details have emerged about Nolen, a former criminal who had served time for assaulting a police officer, it has become clear that he had been seduced by militant ideology.

His Facebook page shows he changed his name to Jah'Keem Yisrael and his cover photo shows Islamic fighters brandishing weapons.

Nolen's posts include pictures of himself in Islamic dress, quotes from religious texts and a vague reference to a "day of judgement" or end-of-the-world event.

This prompted Moore police to call in the FBI to investigate a possible jihadist dimension to the crime.

"We not only had no idea who this person was, we have not have any indication that we have any type of activity like this whatsoever in our city," says Moore police information officer, Sergeant Jeremy Lewis.

"How premeditated it was, that's what's under investigation."

Rumours and unconfirmed accounts of Thursday's events have also started to emerge.

One rural Oklahoma newspaper has reported that Nolen was fired after he got into an argument about the need to stone women if they violated Islamic law.

Another unconfirmed eye-witness report has claimed Nolen was shouting Islamic verses as he beheaded his victim.

One fact is clear. Nolen did visit the main mosque in Oklahoma City.

A picture on his Facebook page shows him standing inside the front entrance flanked by two men and holding up his index finger in a gesture that has become associated with Islamic State militants.

But worshippers inside the affluent and well-attended mosque are quick to distance themselves from the photographs.

"I remember him being here and I remember him asking for the photo to be taken," says one man, who does not want to be identified.

"I know the men standing on either side of him. But they didn't know Nolen. They thought it was strange he asked for a photo." He says the mosque often attracts men who have converted to Islam in jail, as Nolen appears to have done, but do not fully understand what the religion means.

The mosque's imam, Imad Enchassi, also plays down the relevance of Nolen's one-finger gesture.

"The one-finger gesture is made in prayers to bear witness to only one god," he says. "Throughout history in Europe, people have raised one finger to show they are Muslims. Malcolm X used it. It doesn't represent the Islamic State."

Nolen's crime has angered the city's mainly middle-class Islamic community, says Saad Mohammed, an African-American Muslim who is the chairman of the Oklahoma chapter of the Council on American Islamic Relations.

The state is home to immigrants from Pakistan and the Middle East who have come to work as doctors and engineers, or to study at university.

Mohammed said it was his duty to keep an eye on worshippers and he would be happy to give information to the police if he felt something was wrong.

"You have to be aware of people that come, whether you know them or not, to look out for new faces, to keep an eye out for people's conversation," he says.

"Nolen is just one of those guys who just got under the radar, who just slipped right under there and boom, he's front page news."

If Nolen was acting alone, he could be what Oklahoma University Middle East scholar, Joshua Landis, describes as a "psychotic copycat".

"Here we are with our intelligence spread out to get returning jihadis and yet the psychotic copycats are the real danger," he says.

The violent images posted on social media by Islamic militants could easily destabilise people who have no connection to Middle East, Landis says. The IS videos showing the beheading of American citizens James Foley and Steven Sotloff had a huge impact in the US.

"People who clearly feel paranoid or have delusions of grandeur may want to participate in some greater drama," suggests Landis.

Whatever the FBI investigation discovers about Nolen's motives, it may be hard to undo the distrust now felt by Oklahoma's majority Christian population against Muslims.

It is a distrust that was already brewing after recently reported comments by state senator John Bennett, describing Islam as "a cancer" - though Bennett has since distanced himself from the word.

"I think this heightens what people already think about Islam," says Jacob, who lives close to Vaughan Foods, and only wanted to give his first name. "It's geared towards violence."

Muslim leaders say they have already received hate mail and threatening phone calls.

"I have two daughters and a niece and nephews and when this happened, I asked them to keep a low profile," says local restaurant owner Yousef Elyassin.

"You never know about crazy reactions."

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