Trump approves firing squad execution of Nidal Hasan, who killed 13 in 2009 mass shooting

US President Donald Trump has approved the execution by firing squad of former Army Major and psychiatrist Nidal Malik Hasan, who was convicted of killing 13 US service members in a 2009 mass shooting at Fort Hood, Texas. If carried out, it would be the first US military execution since 1961. Firing squads are currently authorised in five US states.