President Donald Trump has approved the execution of former US Army Major Nidal Malik Hasan, who was sentenced to death for the 2009 shooting at Fort Hood, Texas.

The Pentagon announced the decision after Defence Secretary Pete Hegseth recommended that Hasan be executed by an Army firing squad. The Secretary of the Army is expected to determine the date and location of the execution.

Hasan, a former Army psychiatrist, was convicted by a military court in 2013 over the attack, which left 13 people dead and 32 others wounded. He received a death sentence following his conviction on multiple murder and attempted-murder charges.

The November 2009 attack took place at a military facility where soldiers were undergoing processing ahead of overseas deployments. Hasan was arrested after the shooting and remained in military custody while pursuing legal challenges to his conviction and sentence.

If carried out, Hasan’s execution would be the first death sentence implemented by the US military since 1961. The last military execution took place that year, when Army Pvt. John A. Bennett was executed at Fort Leavenworth.

The approval does not set an immediate execution date. Further legal proceedings could affect when the sentence is carried out, while military authorities complete the remaining procedures.

Hasan is currently held at the US Disciplinary Barracks at Fort Leavenworth, Kansas, where he remains on military death row.

The case places renewed attention on the rarely used US military death penalty, which has not been carried out for more than six decades.