‘Draw Muhammad’ shooting in Texas: 5 things to know

Texas police shot dead two gunmen armed with assault rifles who opened fire outside of a “Draw Muhammad” contest organized in the town of Garland on Sunday.

Federal law enforcement sources on Monday confirmed that one of the suspects in the shooting is Elton Simpson. The second suspect is Nadir Soofi, who is Simpson’s roommate, senior law enforcement officials told NBC News. Their apartment was being searched in North Phoenix. At this point, it is unclear whether the suspects were linked to international terror groups, but federal agents are investigating.

Simpson was known to the FBI and was convicted of lying to federal agents five years ago about his plans to allegedly join a terror group in Africa.

Here’s a look at what we know about the incident — from the event to the attackers.

Who organized the event? The inaugural Muhammad Art Exhibit and Contest offered a $10,000 prize for cartoons of the Islamic prophet — depictions that are considered blasphemous by many Muslims around the world.

The event was sponsored by the American Freedom Defense Initiative (AFDI) and attended by its president and co-founder, Pamela Geller — who is also president of Stop Islamization of America (SIOA). Both are listed as hate groups by the Southern Poverty Law Center (SPLC).

What happened? Officials said about 200 people attended the heavily policed event at the Curtis Culwell Center in the Dallas suburb of Garland. As the event was drawing to a close, two gunmen armed with assault rifles drove up to the venue and began shooting, wounding school district security guard Bruce Joiner in his lower leg. Garland police officers returned fire, killing the men.

Why was it held at a school arena? The Curtis Culwell Center was chosen because it had previously hosted an Islamic conference — Stand With the Prophet in Honor and Respect — in January. That event was held one week after gunmen in France attacked and killed 12 people at the Paris offices of Charlie Hebdo, a satirical magazine that had published cartoons depicting Muhammad. The AFDI picketed the January conference and moved to hold its own event.

Who was behind the attack? Federal law enforcement sources confirmed that one of the suspects in the shooting is Elton Simpson. The second suspect is Nadir Soofi, who is Simpson’s roommate, senior law enforcement officials told NBC News. Their apartment was being searched in North Phoenix. At this point, it is unclear whether the suspects were linked to international terror groups, but federal agents are investigating.

Why cartoons? It was not immediately clear if the gunmen were specifically targeting the event. However, the publication of cartoons of Muhammad has triggered violence in the past. Danish newspaper Jyllands-Posten’s publication of a series of Muhammad drawings in September 2005 led to the burning of the Danish flag and attacks on Danish embassies around the Middle East. Cartoonist Kurt Westergaard was attacked at his home in 2010 by a Somali Muslim carrying an ax and a knife.

Paris magazine Charlie Hebdo, which repeatedly published Muhammad cartoons, was attacked on Jan. 7 by armed gunmen who killed 12 people.

The Dallas-Fort Worth chapter of the Council on American-Islamic Relations said it was “very closely monitoring” the situation.

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