The Islamic State in Iraq and Syria (ISIS) is claiming responsibility for the attack at a “Draw Muhammad” contest in Texas.
{mosads}ISIS made the claim on its official radio station on Tuesday morning, according to CNN. It praised the two shooters as “brothers” and warned of future attacks on the American homeland.
“We say to the defenders of the cross, the U.S., that future attacks are going to be harsher and worse,” the radio announcement said, according to CNN.
“The Islamic State soldiers will inflict harm on you with the grace of God. The future is just around the corner.”
U.S. officials have not confirmed the terror group’s claim in Sunday’s attack.
If ISIS ties are confirmed, it would be the group’s first attack on the U.S. mainland. But ISIS could also be looking to legitimize an unrelated attack and add to its propaganda by taking credit for it.
The two gunmen started shooting at an event outside of Dallas held by the American Freedom Defense Initiative, which gave a prize to the best drawing of the Muslim Prophet Muhammad. Many Muslims find visual depictions of Muhammad offensive, and the group is listed as an extremist anti-Muslim group by the Southern Poverty Law Center.
The gunmen, Elton Simpson and Nadir Soofi, shot a school security guard in the ankle before they were killed by law enforcement at the event. Media reports have linked Simpson to terrorism investigations, including an attempt to travel to Somalia for “jihad.”