FBI agents Monday searched through the home of killed Texas gunman Elton Simpson, a man whom they had placed on their watch-list previously for possible ties to terror.
Simpson, of Phoenix, Arizona, had once been convicted of lying to the FBI about a planned trip to Africa, but a judge turned away agents' allegations he was going there to hook up with a terrorist group.
Simpson had been on the FBI’s radar for a decade. Agents once hired an informant at Simpson’s mosque to find if he had any terrorist plans, according to court records.
Simpson was recorded telling the informant he had wanted to travel to Somalia to join radical fighters, federal agents said.
“People fighting and killing your kids, and dropping bombs on people that have nothing to do with nothing,” Simpson allegedly told the informant. “You got to fight back, you can’t be just sitting down.”
It's believed Simpson tweeted out a #TexasAttack message about 30 minutes before the "Draw Muhammad" shooting that left an unarmed security guard injured. The tweet, from "Shariah is Light," the Daily Mail reported: "The bro with me and myself have given bay'ah to Amirul Mu'mineen. May ALlah accept us as mujahideen." ISIS supporters say "Shariah is Light" is the name one of the gunmen used on Twitter.
Simpson and his roommate, who's not yet identified, were killed within minutes of firing their shots.
Police are currently sweeping through Simpson's apartment, using a robot to sift through his home for clues and possibly explosives. One of the suspect's vehicles left at the Texas scene had "what appears to be explosion damage," FOX4Terry tweeted, alongside a picture of a black sedan with obvious signs of damage, the Daily Mail reported.
Meanwhile, the SITE Intelligence Group reported at least one ISIS terrorist made a Twitter claim the Texas attack had been conducted by two individuals who supported the terror group. Specifically, a jihadist called Abu Hussain AlBrilani, identified by SITE as a British man named Junaid Hussain, wrote: "2 of our brothers just opened fire" at the "Draw Muhammed" free speech contest in Garland, Texas, the Daily Mail reported.
The tweet went on: "They Thought They Was Safe in Texas From The Soldiers of The Islamic State."
It's not been confirmed by investigators the attackers were Muslim.
Garland police officer Joe Harn declined at a press conference late Monday morning to confirm any terror ties or draw any motive to radical Islamism.
"We don't know their intent other than they were willing to ... shoot police," he said. "There'a a lot of things I know are going out ... but we are not releasing any names at this time."
Harn also said "this is not going to be a real fast investigation."
He said the two men pulled into the parking lot and exited their vehicle, both brandishing "assault rifles," which they proceeded to fire at nearby officers. The police returned fire and shot and killed the men immediately. Nearby SWAT officers heard the gun fire and responded to the lot and helped to secure it.
Shortly after, police secured and expanded the crime scene, evacuating some nearby buildings in their search for bombs. They didn't find any bombs in the shooters' car, he said.
Harn also confirmed the guard who was shot has been treated and released from the hospital for a leg injury.
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