BEIRUT (TheBlaze/AP) — The Islamic State group claimed responsibility for an attack at a center near Dallas, Texas, exhibiting cartoon depictions of the Prophet Muhammad.
FBI crime scene investigators document the area around two deceased gunmen and their vehicle outside the Curtis Culwell Center in Garland, Texas, Monday, May 4, 2015. Police shot and killed the men after they opened fire on a security officer outside the suburban Dallas venue, which was hosting provocative contest for Prophet Muhammad cartoons Sunday night. (AP/Brandon Wade)
An audio statement on Tuesday on the extremist group's Al Bayan radio station said that "two soldiers of the caliphate" carried out Sunday's attack in Garland. It did not provide details and it was unclear whether the group was opportunistically claiming the attack as its own.
The IS statement says: "We tell America that what is coming is more bitter and harder and you will see from the soldiers of the Caliphate what harms you."
On Monday, there were hints that members of the Islamic State group were involved in the attack where a contest was being held featuring cartoons of Muhammad.
The two suspects in Sunday's attack in the Dallas suburb were shot dead after opening fire outside the center. As the investigation continues, one of the men was identified as the subject of an FBI terror investigation.
In 2010, authorities arrested Elton Simpson in Phoenix as the target of a terror investigation that had begun some four years earlier. Despite an investigation that involved more than 1,500 hours of recorded conversations, including Simpson's discussions about fighting nonbelievers for Allah and plans to link up with "brothers" in Somalia, the government prosecuted him on only one minor charge — lying to a federal agent. He faced three years of probation and $600 in fines and court fees.
Then, on Sunday, two men whom authorities identified as Simpson and Nadir Soofi opened fire in the Dallas suburb of Garland on an unarmed security officer stationed outside the cartoon contest. The officials spoke only on condition of anonymity because they were not authorized to discuss the investigation by name.
The deliberately provocative contest had been expected to draw outrage from the Muslim community. According to mainstream Islamic tradition, any physical depiction of the Prophet Muhammad — even a respectful one — is considered blasphemous, and drawings similar to those featured at the Texas event have sparked violence around the world.
Simpson and Soofi were wearing body armor, and one shot the security officer in the leg. Garland police spokesman Joe Harn said Monday that a single Garland police officer subdued the two gunmen but that after his initial shots, SWAT officers nearby also fired at the two men. Harn said police don't know who fired the lethal shots.
Homeland Security Secretary Jeh Johnson said in a statement Monday that law enforcement authorities are still investigating the men's motives and all circumstances surrounding the attack.
A convert to Islam, Simpson first attracted the FBI's attention in 2006 because of his ties to a former U.S. Navy sailor who had been arrested in Phoenix and was ultimately convicted of terrorism-related charges, according to court records.
In the fall of that year, the FBI asked one of its informants, Dabla Deng, a Sudanese immigrant, to befriend Simpson and ask for advice about Islam.
Over the next few years, Deng would tape his conversations with Simpson with a hidden recording device accumulating more than 1,500 hours of conversations, according to court records.
"I'm telling you, man, we can make it to the battlefield," Simpson is recorded saying on May 29, 2009. "It's time to roll."
In court, prosecutors presented only 17 minutes and 31 seconds during Simpson's trial, according to court documents.
"I have to say that I felt like these charges were completely trumped up, that they were just trying to cover up what had been a very long and expensive investigation and they just couldn't leave without some sort of charges," Simpson's attorney, Kristina Sitton, said.
Sitton described Simpson as so devout that he would not even shake her hand and would sometimes interrupt their legal meetings so he could pray. She said she had no indication that he was capable of violence and assumed he just "snapped."
Less was known about Soofi, who appeared to have never been prosecuted in federal court, according to a search of court records.
Soofi's mother, Sharon Soofi, told KHOU-TV that while her son was a practicing Muslim, he wasn't in the extreme sense.
"Must have just brainwashed him," she told the news station of what must have happened to lead to her son's actions Sunday. "I'm not saying he's that gullible, but to be convinced to do something like this is beyond me."
She added, "I don't fault the police man that shot and killed him. He was just doing his job."
The Associated Press contributed to this report.