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The White House said Tuesday an "act of terror" happened Sunday night outside Garland's Culwell Center, but it's "too early to say" if the Islamic State was involved as the group claimed.
White House spokesman Josh Earnest said Tuesday that the IS group and others were trying to capitalize on social media to radicalize people in the U.S.
Earnest said U.S. officials were aggressively working to counter those efforts, and "it's something that we continue to be vigilant about."
When asked if the Islamic State group has now come to the U.S., Earnest said: "We would certainly want to make sure that we know a whole lot more about the facts" before drawing such a conclusion.
Two gunmen opened fire Sunday night outside the event center hosting the event in Garland where a Muhammad art contest was being held.
Both suspects – Elton Simpson and Nadir Soofi – were killed by a Garland police officer. A security guard was also injured in the incident.
The Associated Press contributed to this report.