Alton Nolen was charged Tuesday with first-degree murder and assault in the decapitation of a former co-worker at a processing plant in Oklahoma. He could face the death penalty, a county prosecutor said.

The gruesome nature of the attack coupled with the religious adherence of the suspect has attracted significant attention to the case, from well beyond the borders of Moore, a community previously known for a devastating EF5 tornado that killed more than two dozen people and destroyed 1,000 homes.

The beheading has also sparked endless speculation — not to mention considerable debate over what to call it.

Here’s what we know about Nolen so far.

Nolen was suspended just before the attack

Police originally said that Nolen, 30, entered a Vaughan Foods processing plant on Thursday afternoon shortly after being “terminated.” But in an affidavit released Tuesday, police said Nolen had actually been suspended just before the incident.

He then went home, the affidavit said, and grabbed “a large bladed knife.” At that point, according to Cleveland County Prosecutor Greg Mashburn, Nolen “returned to get revenge.” In the plant’s administrative office, police say, Nolen attacked 54-year-old Colleen Hufford from behind and severed her head from her body.

Nolen then attacked 43-year-old Traci Johnson, another employee, before he was stopped by the company’s chief operating officer, Mark Vaughan. Vaughan, a reserve deputy with the Oklahoma County Sheriff’s Department, shot Nolen with a rifle, stopping the attack. Both Nolen and Johnson were hospitalized.

Johnson was released from the hospital Saturday, after receiving treatment for multiple stab wounds. Nolen remains in stable condition.

The police affidavit said Nolen was suspended after Johnson initiated a complaint. According to Mashburn, the prosecutor, Johnson complained following an argument “about [Nolen] not liking white people.”

He has a criminal record

Nolen was convicted on drug charges, and for assault and battery of a police officer and escape from detention in 2011. He served two years of a six-year sentence before being released in 2013, according to Oklahoma Department of Corrections records.

Department of Corrections spokesman Jerry Massie told the Associated Press that Nolen earned an early release because of his good behavior (he had no misconduct reports during his time in prison) and for completing two programs aimed at teaching coping and transition skills to inmates before they re-enter society. Nolen also received credit for time served in a county jail before his conviction.

Nolen is a Muslim convert

A Moore police spokesman told reporters last week that the department enlisted the help of the FBI because of Nolen’s religion, his recent proselytizing efforts and the nature of the crime. “Information was obtained that he recently started trying to convert several employees to the Muslim religion,” Moore Police Sgt. Jeremy Lewis said in a statement on Friday.

The statement continued: “Due to the manner of death and the initial statements of co-workers and other initial information, the Moore Police Department requested the assistance of the FBI in conducting a background investigation on Nolan.”

State Department of Corrections records indicate that Nolen has a handful of religious tattoos, including one of an Arabic greeting that translates to “peace be upon you.” He also has a “Jesus Christ” tattoo and one of praying hands, according to the offender record.

His Facebook page — which a federal law enforcement official described to The Washington Post as “provocative” — featured, among other things, a photo of Osama bin Laden. The wide range of photos available on the page also included a depiction of a beheading, and several messages pertaining to Islam.

Nolen’s relatives told the Associated Press that the suspect grew up in a non-denominational, Christian church. It is believed he converted to Islam during his incarceration.

A prominent Muslim leader in the Moore area told the Oklahoman that several attendees of his mosque remember Nolen visiting for prayers. Saad Mohammad, a spokesman for the Islamic Society of Greater Oklahoma City, denounced Nolen’s attack, saying it went against the principles of Islam. “He is as far away from Islam as he can be,” Mohammad said.

Mohammad added that the Islamic Society stepped up security at the facility in the wake of Nolen’s workplace attack, as a precaution against any potential retaliation targeting their community.

The FBI is treating the case as “workplace violence”

Nolen’s religious adherence and the fact that the victim was beheaded have led some — including Texas Gov. Rick Perry — to question why law enforcement officials and the media have not called the attack a “terrorist” act.

“Any rational-thinking American,” Perry said Monday, “is going to look and this and go this is more than just normal workplace violence.” Similarly, a group of eight Oklahoma state House representatives calling themselves the “Counterterrorism Caucus” released a Monday statement using the beheading to call for a “public discussion about potential terrorists in our midst and the role that Sharia law plays in their actions,” as the Oklahoman reported.

However, the question here isn’t as simple as a hunch based on reported details. For instance, the FBI uses a specific definition of terrorism in its investigations. In order to be considered a terrorist act, an instance of violence must “appear intended (i) to intimidate or coerce a civilian population; (ii) to influence the policy of a government by intimidation or coercion; or (iii) to affect the conduct of a government by mass destruction, assassination. or kidnapping.”

This, presumably, is partly why the FBI is not currently treating the alleged attack as a terrorist act. Speaking to The Post, two federal law enforcement officials said the FBI was currently looking at the attack as an instance of workplace violence, and that there’s no indication Nolen was mimicking the recent beheadings carried out by the Islamic State.

The Post’s Mark Berman took a closer look at the debate over what to call attacks like this one.

Mashburn, the prosecutor, said at a press conference Tuesday that the attack appeared to be about revenge, not religion.

“It had more to do with race rather than trying to convert people,” Mashburn said, according to the AP.

Nolen’s family is ‘in shock’

After the attack, Nolen’s mother and sister spoke out in a Facebook video message. “My heart is just so heavy right now,” his mother said. “I want to apologize to both families because this is not Alton.”

The attack, she said, was out of character for her son. “I know my son. My son was raised up in a loving home,” Joyce Nolen said. “My son was raised up believing in God. That’s what he believed.”

The mother of Alton Nolen, the man suspected of beheading a former co-worker and attacking a second at an Oklahoma food-processing plant, has released a video statement via Facebook. In the video, Joyce Nolen says, "There are two sides to every story.” (The Washington Post)

Karla Dunn, who grew up with Nolen and his younger siblings, said in an interview with KOCO that she remembers a younger Nolen as “very polite. He was, you know, very humble. His whole family was very polite, very humble.” She added, “He was really just a normal person.”

Nolen’s sister, Megan Nolen, said the family was “still in shock,” adding: “We’re praying for both of the victims’ families.”

[This post has been updated multiple times.]