Islamic State claims responsibility for Texas attack

Show Caption Hide Caption Islamic State claims responsibility for Texas attack The Islamic State terrorist organization is claiming responsibility for an attack in Garland, Texas where there was an exhibit of cartoon depictions of the Prophet Mohammed. The suspects' families are denouncing the attack.

The Islamic State claimed responsibility Tuesday for the attack outside a Texas art show showcasing cartoon depictions of the prophet Mohammed, but it was not clear how much involvement the group actually had.

A statement read on the group's Al Bayan radio station said that "two soldiers of the caliphate" carried out Sunday's attack, the jihadist monitoring service SITE Intel Group said.

If true, the attack would mark the first time the Islamic State has claimed responsibility for an attack on U.S. soil. It was not clear Tuesday if Islamic State leaders had any knowledge of the attack before it took place Sunday night at the Mohammed Art Exhibit event in Garland.

White House spokesman Josh Earnest said officials don't know if the Islamic State's claim of responsibility for the attack in Garland, Texas, is legitimate.

"This is still under investigation" by the FBI and other agencies, Earnest said. "It's too early to say at this point."

Earnest also praised law enforcement officers for their efforts to "foil what appears to be an attempted terrorist attack."

A federal law enforcement official told The Associated Press that authorities had an open investigation into Simpson at the time of the shooting. The official, who was not authorized to discuss it and spoke on condition of anonymity, said investigators will be studying contacts the men had prior to the shooting, both with associates in the U.S. and abroad, to determine any terror-related ties.

The statement from Islamic State, also known as ISIS or ISIL, said: "We tell … America that what is coming will be more grievous and more bitter and you will see from the soldiers of the Caliphate what will harm you, God willing," the Associated Press reported.

The Council on American-Islamic Relations, the nation's largest Muslim civil rights and advocacy organization, condemned the attack as "more insulting to our faith than any cartoon."

Police said the suspects drove to a parking lot entrance at at the event site, the Curtis Culwell center in the Dallas suburb of Garland. A patrol car blocked the entrance to the lot, so the men got out of their car and began shooting, Garland police spokesman Joe Harn said.

A security guard in the patrol car was wounded in the leg. Police killed the attackers, identified as Phoenix residents Elton Simpson, 30, and Nadir Soofi, 34.

The exhibit, hosted by the American Freedom Defense Initiative, featured "images of Islam's prophet, both historic and contemporary, and speeches by leading voices of freedom and internationally renowned free speech advocates," according to a news release from the group.

According to Islamic tradition, any physical depiction of the prophet Mohammed — even a respectful one — is considered blasphemous.

On April 23, a Minneapolis man who joined the Somalia-based al-Shabad jihadist group called on "brothers" to attack the Texas exhibit, invoking the January bloodbath at the French satirical newspaper Charlie Hebdo, Minnesota Public Radio reported.

"The brothers from the Charlie Hebdo attack did their part. It's time for brothers in the #US to do their part," Mohammed Abdullahi Hassan wrote on Twitter, with a link to the Garland event.

Known as Mujahid Miski on social media, Hassan also tweeted photos Amedy Coulibaly, a friend of the Charlie Hebdo killers who attacked a Jewish market in Paris two days later, plus photos of two men from Minneapolis who died carrying out terrorist attacks in Somalia.

"If only we had men like these brothers in the #States, our beloved Muhammad would not have been drawn," Hassan tweeted, according to MPR.

A Somali leader in Minneapolis told KARE-TV the community was "not surprised" by Hassan's call to arms.

"He's very well followed through the social media, very well known," he said, noting that Hassan has changed names often. MPR said Twitter had suspended 31 accounts Hassan opened under different identities.

"The real concern we have is that some individuals are buying their messages," he said. "They're listening to them, and that's where the concern is."

Relatives of the Texas gunmen expressed bewilderment at the attack. Simpson's family issued a statement calling the attack an "act of senseless violence" and saying family members were "heartbroken and in a state of shock."

Simpson is believed to have tweeted several ominous messages before the Garland incident, using the hashtag #texasattack.

He was indicted in January 2010 for lying to the FBI in a terrorism investigation when he told federal investigators he had not discussed traveling to Somalia to engage in "violent jihad," federal court papers show. He was convicted a year later and sentenced to three years probation.

Soofi's mother told WFAA-TV in Dallas Fort Worth her son was a passionate defender of Islam -- but in no way violent.

Soofi, who left behind an 8-year-old son, owned a carpet-cleaning business, according the Arizona corporate records. He previously owned Cleopatra's Pizza Bistro, a 40-seat restaurant in north Phoenix, that served halal, or Islamically permissible, food.

Court records show he was sued twice for allegedly stealing pay-per-view broadcasts of Ultimate Fighting matches and showing them to patrons at the restaurant. He lost the lawsuits by default and was ordered to pay damages of several thousand dollars.

"He's not a terrorist. He was kind, he was devoted to his son, and I still can't believe he would try to hurt anybody," his mother said.. "I just can't."

Contributing: David Jackson and Michael Winter, USA TODAY, and Marie Saavedra, WFAA-TV Dallas-Fort Worth