Garland shooting: Twitter suspends account that warned about a 'Texas attack' 15 minutes before incident at anti-Muslim event

Account appeared to show allegiance to both al-Qaeda and Isis

A police officer directs the evacuation of attendees of the Muhammad Art Exhibit and Contest, after a shooting outside the Curtis Culwell Center where the event was held in Garland, Texas on 3 May. (Reuters)

Twitter appears to have suspended an account that tweeted about an attack in Texas 15 minutes before shots were fired at an anti-Muslim event in the city of Garland.

Two gunmen were killed by police officers at the event which encouraged participants to submit cartoons of the Prophet Mohamed, offering a $10,000 prize for the “best”.

The suspended account had an avatar picture depicting the US-born radical Islamist cleric and senior al-Qaeda leader Anwar al-Awlaki, who was killed in a drone strike in September 2011.

ISIS supporters claimed on Twitter that one of the gunmen was a man calling himself Shariah Is Light, but police hasn't confirmed yet. (Twitter)

Under the profile name “Shariah is Light”, the tweet read: “The bro with me and myself have given bay’ah to Amirul Mu’mineen. May Allah accept us as mujahideen [jihadists]. Make dua. #texasattack.”

The tweet was posted at 6.35pm local time in Texas – 15 minutes before Garland Police Department received its first reports of gunfire at the anti-Muslim event. In a tweet sent three hours before its last, the profile recommended people follow another account - @AbuHu55ain – which has also now been suspended.

According to Guardian Australia, previous tweets posted by the account before it was suspended appeared to support the actions of the Isis militant group in the Middle East. The reference to giving "bay'ah to Amirul Mu'mineen" literally means pledging allegiance to the "Commander of the Faithful" - a possible reference to the leader of the so-called Islamic State, Abu Bakr al-Baghdadi.

Other tweets reportedly suggested the account belonged to a recently-converted Muslim, including comments like "I don't know Arabic" and "my fam didn't trip when I became a Muslim".

Police are yet to formally identify the two gunmen involved in the attack – in part because they have been unable to remove their bodies from the scene. Garland police spokesman Joe Harn said they lie too close to the attackers’ car, which is being carefully checked for explosives.

The suspects' vehicle was searched for explosives. (Fox News)

The car is getting searched for explosion damage. (Twitter/Fox4Terry)

But a senior FBI official told ABC News one of the suspects is thought to be Elton Simpson, an Arizona man known to the federal agency from a previous terror investigation.

FBI agents view the area where the shooting suspects lay behind a blue covering. (Getty Images)

The unnamed official claimed the FBI believes Simpson to be the man behind the suspended Twitter account, and added that nothing is yet known about the second shooter.