Texas police are looking into whether a shooting at a Muhammad cartoon contest was a terrorist attack

In a press conference on Monday, the police department in Garland, Texas said it was investigating whether two men responsible for a shooting outside of a conference featuring a prophet Muhammad cartoon-drawing contest had ties to terrorist groups.

"We are certainly looking into that," police spokesman Joe Harn said in a press conference, which The Hill reported on. "We have not knocked that out."

Two men were killed by police after they allegedly shot a security guard outside of the event, hosted by controversial group American Freedom Defense Initiative, considered an anti-Muslim group by the Southern Poverty Law Center.

Inspired by attacks on French satirical newspaper Charlie Hebdo, the event also hosted a speech by Dutch politician Geert Wilders, who has repeatedly criticized Islam, prompting some US lawmakers to attempt to bar him from entering the country.

Speculation about the shooting's link to terrorism comes after revelations that one of the alleged shooters, Elton Simpson, had possibly attempted to join a terrorist organization. In 2010, Simpson was convicted of lying to the FBI about his plans to travel to Somalia, but a judge ruled that it couldn't be proved that he was attempting to travel there to commit terrorism.

Shortly before the shooting, an account that has spoken in support of extremist groups like ISIS tweeted that there would be a terrorist attack in Texas, the Guardian reported.