President Donald Trump has approved the execution by firing squad of Nidal Malik Hasan, the terrorist who murdered 13 people in a 2009 shooting spree at Fort Hood, Texas.

The decision followed a recommendation by Defense Secretary Pete Hegseth. The Pentagon said the date and location of the execution will be determined at a later time. “Hasan’s day of reckoning has finally arrived," the Pentagon said in a statement.

If carried out, the execution would mark the first time since 1961 that the US military has carried out a death sentence itself.

Hasan, now 56, was a US Army officer and psychiatrist. He was born in the US to a Palestinian family that had immigrated from Samaria and maintained ties with relatives in the region over the years.

On November 5, 2009, Hasan arrived at a medical clinic at Fort Hood that served, among others, soldiers preparing for deployment to Iraq and Afghanistan. Armed with two handguns and ammunition he had prepared in advance, he opened fire on those inside while shouting “Allahu Akbar."

Thirteen people were killed, including 12 soldiers, and 32 others were wounded. The shooting ended when a civilian police officer shot and subdued Hasan, leaving him paralyzed from the waist down.

In 2013, a military jury convicted Hasan and sentenced him to death. He represented himself during the trial, made no attempt to deny his actions and declined to call witnesses in his defense.

Trump’s approval now removes a major obstacle to carrying out the sentence, after Hasan spent more than a decade on death row within the military justice system.