President Donald Trump has approved the execution by firing squad of Army Maj. Nidal Malik Hasan for the 2009 shooting rampage at Fort Hood, Texas. The U.S. military has not carried out an execution since 1961.

Pentagon spokesperson Sean Parnell announced the decision in a post on X, stating, “Judgement day for Hasan has finally come.” The Army secretary will determine the time and place for the execution.

Hasan, an Army psychiatrist, opened fire with a handgun in a medical building at Fort Hood, shouting "Allahu akbar"—Arabic for “God is great!”—killing 13 people and injuring more than 30. During his trial, Hasan stated it was an effort to stop soldiers from deploying to Afghanistan and harming Muslims, and he described himself as a soldier who had “switched sides.”

Trump’s approval initiates procedural steps toward carrying out the execution. However, Hasan may challenge the sentence through a habeas corpus appeal in the civilian federal court system, which could delay the execution for years, according to an article published in the Army Lawyer magazine.

Death sentences are rare in the military justice system, and executions are even rarer. Four individuals, including Hasan, are currently on military death row at Fort Leavenworth, Kansas. A previous death sentence approved by President George W. Bush for Army Spc. Ronald Gray in 2008 was put on hold by a judge and remains pending.

The last military execution occurred in 1961 when Pvt. John Bennett was hanged for raping an 11-year-old girl.

Trump's decision comes after a recent failed attempt to execute Christa Pike by lethal injection in Tennessee, which prompted the state's governor to halt further executions for the year and order a review. Trump resumed federal executions after an informal moratorium, with the federal government executing 13 people between 2020 and early 2021, making his administration the most prolific in terms of executions in over 130 years.