WASHINGTON — The Army Reserve officer killed in the Orlando night club mass murder Sunday might qualify for a Purple Heart if the ongoing law enforcement investigation finds the attack was inspired by the Islamic State group, the Pentagon said Thursday.

Army Reserve Capt. Antonio D. Brown, 30, was one of 49 people killed and more than 50 others seriously wounded when Omar Mateen, 29, opened fire early Sunday morning at an Orlando nightclub. Mateen had pledged allegiance to the Islamic State group prior to his attack on Pulse, a gay nightclub, according to news reports.

Whether the incident qualifies Brown for a Purple Heart depends on what federal law enforcement officials determine was the motivation for the attack. In the days since the attack, officials have questioned whether Mateen was motivated by anti-gay sentiments or inspired by the terrorist group.

Peter Cook, the Pentagon press secretary, said Thursday that whether Brown would qualify “has to do with the definition of the event, the Justice Department’s own determination of what was carried out there -- so it’s not necessarily in our hands in terms of the formal designation.”

The Purple Heart medal and recognition carries specific monetary and military burial rights, but until recently was limited to injuries sustained in combat.

In 2014, Congress changed the criteria for the award to be able to honor the military personnel killed or injured in the 2009 Fort Hood attack. In the newer criteria, a military person can qualify for a Purple Heart for non-combat injuries or death on domestic soil if the attacks were determined to be inspired by or conducted by a foreign terrorist organization.

In late 2015, the Navy awarded the Purple Heart to five military members killed in the July 2015 shootings at two naval centers in Chattanooga, Tennessee. The award of the Purple Heart had been on hold for months pending the determination by federal law enforcement officials that the attack was inspired by terrorists.

copp.tara@stripes.com

Twitter: @TaraCopp